Crank No Start That No One Could Fix SBQM Free Video!

[@EricJackson-e9l]

I've been in a mentally abusive relationship for 7 years now and been trying to get my truck running for the last 6 months thank you for your video and definitely help me get out of the relationship that I'm in and moved on to a better place❤❤

[@SchrodingersBox]

Well sorry to hear that but glad my video helped!!

[@joenunya8449]

If your truck is mentally abusing you, you should definitely sell it, or maybe even donate it to a charity.

[@lbxshow5271]

Been watching you for a while. Magnificent teaching 😊

[@MichaelRodriguez-wk4nd]

Hold Ur head up n get out of there asap

[@erikkirby1]

as a 25 years auto tech i can tell you we learn everyday! if you are willing to!!!

[@SchrodingersBox]

So true my friend!!!

[@502undergroundmedia6]

@@SchrodingersBox this video popped up in my suggestions and I can honestly say that I learned something. New Subscriber!!! Thanks for the tutorial.

[@miraclechikwem4987]

I like your teaching sir God bless you

[@robbieturnbull4253]

@@SchrodingersBox admitting your wrong when your wrong is the important thing unlike other people who find out what it really was and say oh I knew that all along you admitted your mistake and that’s very commendable I can see why they would of thought it was a crank or cam sensor your not stupid for not checking the ground first you were just performing tests don’t ever feel stupid for making a mistake we all make mistakes and learn from them peace for now my friend awesome video a lot of people won’t admit their mistakes you did that’s the important thing 😊

[@valdabromfield2369]

That's right we learn everyday...that's good troubleshooting...complex problem(s), simple solution(s); simple problem(s),complex solution(s). Very satisfying and rewarding when you solve the problem(s). Appreciate the vid mate n all comments. Be bless

[@riblets1968]

You used your head, applied your knowledge, and fixed the problem. Excellent, sir.

[@SchrodingersBox]

Thanks!! sure beats guessing

[@jamesworsham2312]

Knowledge is the ultimate power. Sometimes we get wrapped up in what we're doing we forget to go back to the basis

[@guledmah5872]

You deserve the best technicians award in the USA

[@brianschumaker5912]

Absolutely. Every dealership should have a diagnostic expert like this on staff!

[@JohnDoesGarage]

I love those kinds of challenges myself. There is a very good friend of mine who is a factory trained technician with decades of experience and he told me he rarely ever sees a sensor failure. According to him the vast majority of the time it is a wiring issue. Case in point. Thank you for your amazing content.

[@SchrodingersBox]

Yes I have only seen 3 in almost 10 years

[@cpcoark]

The first big clue I picked up was the customer stated the no start was intermittent. Then not starting at all. More than likely that would be caused by a bad connection. Temperature affect would be second if it was consistent under hot/cold conditions

[@SchrodingersBox]

9/10 times that’s exactly how a crank sensor fails though. or a sticking IAC, or a failing fuel pump.

[@sandygrungerson1177]

@@SchrodingersBox yes i was curious what your initial opinion was on the cause, given the intermettant description, but i would think your diagnostic would work regardless as you would still see the ground/no-ground condition with the light

[@michaelszczys8316]

@@cpcoark bas connections will really mess with you. I have seen a bad battery connection completely imitate a ' last leg and down to dead ' condition when really it was fully charged and good for 100 cranks.

[@ag1auto588]

Great video you remind me of Scanner Danner.. I've been a mechanic for 20 years, & I agree always start with power and grounds,, btw on Chevys is common to have problems with grounds especially with wiring traveling through parts that vibrate or under exhaust manifolds or close to them. My hat goes off to you sir for calling yourself a do it yourselfer, shows humbleness.👍

[@tshephokgetjepe3162]

There is a reason why I subscribed to your channel, your methodology of fault finding is top notch....all the way from South Africa 🇿🇦

[@SchrodingersBox]

Thank you my friend!!

[@siyanxumalo4230]

🤝🏽

[@dougkelley1266]

Your classes have taught me a lot. I figured bad ground before you called it. Thank you for all you teach

[@KG-vr3te]

Being a tech brings the money in. I do enjoy the characters I work with and landrover/Jaguar sends me many miles away from home on courses to learn the product. This is easily as good as the courses and I love watching from the comfort of my armchair. He talks perfectly to prompt your own mind thoughts. I love it

Over a year ago I had to change the grounding wire clamp to the battery. It was running perfectly before and now been sitting ever since. I was about to sell it for $400 because I did not want to deal with figuring it out. I saw this video and now I got a couple buyers offering me $2000. Thank you so much!!

[@23hublock1]

You have the rare ability to explain complexity in a way that makes sense and is easy to understand. You would also make for a very good lecturer at a university....even just a few hours a week would benefit so many people.

[@SchrodingersBox]

thank you! I have been told this quite often. Maybe a gift.

[@onegurl9]

And hopefully benefit his pocket book too.

[@chicanobluesaz4191]

I knew the problem as soon as I saw the title. Very common issue. Any well versed technician such as yourself should find this issue every time. Good job and great video!

[@mlamont9999]

Can you explain better where this is located

[@chicanobluesaz4191]

Under the driver side exhaust manifold forward of the oil filter adapter, above the oil cooler lines. The ground is bolted to the engine block.

[@mattdebeer5289]

Can you please give me a indication. I have changed my Audi A4 Battery. Same symptoms with the new one. Crank No Start. RPM doesn't move. Right Side Windows don't work. Try to jump start nothing. I'm have codes of lost communication gateway A. Lost communication Cluster Panel. High beams relay clicks hard when I switch it on.

[@chicanobluesaz4191]

@mattdebeer5289 Sorry but I have no experience with Audi so I have no clue as to where the problem could be. It does sound like you have a communication issue though

[@chicanobluesaz4191]

@@mattdebeer5289 You'll need to have a bi-directional scan tool and see what data bus is affected and then additionally what modules you can communicate with. You'll also need a good schematic of the communications network

[@TheDisgruntledMechanic]

Huh! I was wrong! no Pico. But to diagnose with basic tools is awesome! It was the hoodie you were wearing that helped you diagnose this!

[@SchrodingersBox]

it did help or I’d have frozen to death!!

[@InsideOfMyOwnMind]

The hoodie always helps.And if you have the baseball cap underneath it even better.

[@danieljohnson3328]

Two prior crank censors, a cam censor, and you still diagnose it in what I would still call a few minutes. You are Brilliant my friend. I learn something every time I watch your videos.

[@SchrodingersBox]

Glad to hear! Thank you!

[@rgmeyers66]

Thought provoking intelligent content- delivered in a no fluff no nonsense manner. Logic applied over and over again. Thank you for sharing.

[@tinytim9453]

That was beautiful! When it comes to anything electrical, I'm dumber than a box of rocks. But with you, there is something about you that makes it so clear and understanding.

[@SchrodingersBox]

Thank you, that’s what I hope to achieve!! I’m most successful if you can do it!!

[@gilberthale7777]

From earlier on in the video my mind was screaming, "It's a bad ground!" Not just a gut feel, it was more that when you saw the injector signal was firing, and the test light clip on the positive terminal and no test light when you touched the ground circuit wiring, the jig was up. None the less, what a brilliant process, even if you did go to a few more tested areas than "needed." I am glad you did take a longer path to get to your end point, as it gave me a chance to learn more about that GM circuitry. My strength is more in the First Generation Mustangs Shelbys (1966 - 1973), and with Ford systems from the 70s and 80s back when I was working as a Ford tech in SoCal. I can tell you this for sure, your wiring diagrams are superior to the older Ford schematics I had (and still have) to work with, It was not until 1972 that we really began to see fairly decent wiring schematics, and 1973 brought us some even more decent diagrams,. Yet, the wiring schematics you showed are truly superior to the kind of detail I have from my schematics sources (all Ford publications). Anyway, I am a new viewer of your videos. I look forward to seeing more. And, I understand that "rush" when a hard to diagnose problem is finally tracked down and corrected. There was hardly anything more satisfying to me back in the day than figuring out a problem that had gone to so many other technicians, and even other dealerships, before I finally had the problem car come to me. Often the really obscure issues turned out to be ground related. I always enjoyed that logical challenge found in where I chose to begin my diagnostic approach, and why I then chose to go to one "next step" to check as opposed to another one. The logical diagnostic approach I learned in the auto industry served me very well when I went over to the computer industry. I loved solving programming and circuitry issues by applying logic. Now retired, I spend a lot of time sharing things I know about diagnosing and repairing First Generation Mustangs and Shelbys, which are applicable to all older Fords and even other makes. My KZbin channel has feeble content in comparison to what you have, so far. But, considering my narrow focus I am pleased so many folks have found it to be useful. Anyway, I get why you are sharing your videos, and appreciate your sharing back to the industry we love so much. An aside, I also appreciate when you leave in the goofs and erroneous.needless side trips you take in your diagnostic approach. It lets me get a better feel for where your thinking is. And, it lets me know that indeed it is okay to take a needless side path during a diagnostic approach. Some of my more powerful insights have come from taking needless side trips, where I have a happy discovery I can use at some other time. Anyway, Kudos!

[@SchrodingersBox]

Thanks, and yeah I totally can’t believe I didn’t check the ground while I was checking power but like I said, you can get your well poisoned and also it’s really really distracting when you are also filming. Had I not been filing I’d have tested the power and the ground and then checked signal.

[@gilberthale7777]

@@SchrodingersBox No matter, you rock! In the end you found the problem, and even demonstrated proof of the error before locating the point of actual cause of the error.. Who cares if a few extra paths were taken in the meanwhile? It will not be me tossing a rock at you! If I had to choose between efficient and effective, I would choose effective every time.

[@RobertReeves-ce2dq]

😅Omg I am so glad I watched you you are very smart oh shit man I had my 2012 Chevy Tahoe LDZ I got from friend of my he thought moter was lock up after I bought it from him and brought home and be sitting bout 5 months then I start mess with it found out moter not lock up then I try tester under dash said moter is fine and said sumthing is cross over then took me two months try fill out and brought a New battery and put in then moter turn over then o spray start fuild it vrank up went dead got worse then voltage start drop actually fool then I check all the ground wire and til can't fill out and i thought bout watch Utube then I spot that show is said wooo hooo it doing just like my Tahoe and i am thankful thay show me where the problem is i am get dress then fix jack up i hope i hot it oh man thank lot brother you are the best in ever see i am start watching it show man you so damn good man hell yeah you are the master mind brother

[@jviews1]

My family buys old (> 20 years old) cars and I ALWAYS clean all ground straps I find as a week 1 checkout. . This is why. GREAT VIDEO. Loved how you came to the problem root cause..

[@frankvoynar6427]

I'll certainly agree with Matt that feeling never goes away, solving a complex problem than moving on to the next.

[@LorenzoPreston-j8g]

I agree as an electrician

[@bluegem72]

You are the only person that can fix my car. I have a no start for over 3 years. No one can fix it. I tried grounding it just like you did to get it started but it didn't work.

[@SchrodingersBox]

What was the voltage on the ground before you grounded it? How did you know the ground was the problem?

[@graemer66]

Yes solving a problem can give you much satisfaction and save you money too. Thanks to you I've taken up your tried and tested advise to know how the system works otherwise you do not have an understanding on what you are working on. Over here in Australia I've found a lot of mechanics not interested in working on my 1999 Z28 Camaro but with your video's I have been able to solve most of the issues encounted. Thank you your friend in Australia. Graeme Redman

[@SchrodingersBox]

Great to hear! “No Worries” lol.

[@twoshedsjackson6478]

Thanks for another interesting video. Quite coincidentally, this is the second video in a couple of days I've seen on the same subject. South Main Autos channel had a customer asking for a second opinion on whether he really needed to spend the $4000 being asked the manufacturer's main stealer to replace his entire wiring loom. After diagnostic investigation, he too just needed to replace a corroded earth strap on the underside of the engine.

[@shepherdguy]

At the very beginning of the video when you stated the shop had checked and replaced the cam and crank sensors with no luck, I was thinking in my mind you were going to discover a bent or damaged tone wheel, but that thought quickly dissipated when you showed the count and speed. I was not thinking a missing ground. Great information! Love your approach to troubleshooting.

[@SchrodingersBox]

Yeah good thinking on tone wheel- I actually have a video where that was the issue.

[@bludhoun9016]

@@SchrodingersBoxreplaced a transmission on 03 Silverado and now crank but no start . No spark from coils and no fuel from fuel pump . Constant ground from (A) and keyed power from pink . Still no start. Wat could this be that’s not allowing truck to start ?

[@SchrodingersBox]

What is the CKpS signal voltage showing?

[@foreverwood1963]

You know how you can have several teachers that all teach math but you can't pass some teacher's class but there's that one. That's you! It's taught that way. I love to see your videos.

[@SchrodingersBox]

I do know what you mean. Thanks for the compliment.

[@MarzNet256]

I've been binge watching your videos and am learning so much, so fast, it's kinda mind blowing. I've been using a DVOM, a knockoff power probe, and the XTool A30D scanner (same as a D7, but with BT and fewer special functions) and practice with it on my 2006 Matrix with 209k miles.

[@SchrodingersBox]

Great to hear! You will definitely be able to get the most out of those tools for sure. that setup is pretty similar to all I use in 90% of my videos.

[@MarzNet256]

@@SchrodingersBox Thanks!

[@biglevstergarage]

Spectacular job Matt, good find as well. I had a couple experiences like that as well with my scope on a rope too. Someone a while back spent hours with a buddy trying to figure out why his 89 Chevy truck wasn't starting, they took out the fuel pump and half the top side of the engine apart. Truck still didn't start and they spent a good 6+ hours on it and scratching their heads, like why isn't it starting. The guy calls on me to check it out, go to try and start it, no start, look at the dash, no check engine light, pull out the trusty test light look for ECM fuse, blown fuse. They get a new fuse and put it in, starts right up, told them it may blow again depending on what happened to blow it the first time, but started it up a few more times and let it run and it didn't blow the fuse again. Spent under 10 minutes figuring it out, where the guy and his friend spent over 6 hours and half the truck apart trying to figure out what was wrong. Its thanks to many people like yourself on here that taught others like myself what to do, where to look and stuff. Great job!

[@SchrodingersBox]

Great story man!! Thanks for sharing that!!

[@konyoha]

I haven't had any problems with grounding either...but you really add to my knowledge in understanding diagnostic problems. Thank you, teacher

[@at_3831]

I scored very high on the ASVAB test so I was fortunate enough to be trained in aeronautical electrical and mechanical troubleshooting it’s a skill not easily learned but very easy forgotten when not used. This video is extremely knowledgeable information for anyone learning how modern automotive and equipment work.

[@nicklala4982]

Love your logical, rational approach to problem solving. Excellent job!

[@SchrodingersBox]

thank you!!

[@TheCowgirlNiamh]

Fantastic work Matt! 👏👏👏 My initial thought was wiring because you said intermittent but I still would have followed your usual method because it really does help give direction 👍

[@SchrodingersBox]

Good call! Yes there are many many many things that can cause an intermittent that eventually becomes consistent. as you said it’s best to just follow the procedure and whatever it is will be found every time.

[@TheDisgruntledMechanic]

Nice hoodie Matt! Thanks for the shout out. I bet the Pico comes out on this video. Now back to the video.

[@SchrodingersBox]

Hahaha I actually already had it out of the case ready to go but never went that direction!!

[@sheerwillsurvival2064]

Great video great job as usual 👊🏻 I remember as a Chevrolet goodwrench technician back in the 70s 80s living in the rust belt those grounds were always a problem. But I never thought that was the problem on this one looks are deceiving . 👊🏻

[@spelunkerd]

That was a great case, I like the way you took us along to follow your thought process. I was a little puzzled by the wiring diagram, because we don't see all of the electronics there. The wiring diagram notwithstanding, it looks like grounding of the primary side is separate from the PCM, triggered by a simple square wave positive input along the signal wire. That would reduce the chance of inductive voltage spikes reflecting back to the PCM.

[@SchrodingersBox]

Thanks Dave!! Great to see you again!

[@spelunkerd]

I went back and looked at the Alldata wiring diagram for my old 2000 Suburban. It doesn't have as much internal detail but they do say that the trigger for firing is a ground signal that turns on and off inside the PCM. So, ground side switched on the signal wire, at least in my old beast.

[@robertbaker2534]

Hi, this is Robert. Excellent diagnosis on the truck ground! I would LOVE to talk to you about a very perplexing No Crank, No Start issue I have with my 2005 Toyota Avalon XLS. Drove it all day the day before, parked it for the night. Next day saw I needed some air in a tire, plugged in a brand new tire pump into the power outlet in my console. It wouldn't start. I put the key in the ignition, turned it...not a sound, click or anything. My windows, moon roof and radio are not working either. I found a blown 15A fuse for the power outlet and replaced it. I plugged the pump into my truck, works perfectly! My car now, only headlights, dash lights and remote key fob to lock/unlock the car and trunk works. I spent 4 days checking all the other fuses, none are blown. Checked power at the starter relay and got power, switched relays with another one, same results... NOTHING! I gave up and took it to a shop almost a month ago now...their electrical guy has no clue at this point either! I have been without my car for a month now, with no light at the end of the tunnel! I don't have a clue why the fuse blew and why it won't start. The one weird thing the guy at the shop did was took out the relay, put a jumper in and it started right up and he drove it around a while! No problems! I don't know if he checked the windows, radio or moon roof though...he takes the jumper out and puts the relay BACK IN and we're back to the no crank, no start issue! What the heck!!??? The guy at the shop ALSO called a friend of his at the Toyota Dealer...still no joy and it blows his mind too!!! What the heck happened, why did the fuse blow and why is my electrical side DEAD? He did however find high resistance in the Neutral Safety Switch and changed that out...still no joy... HELP!!! Sorry this was so long, but that's what happened from start to finish up to this point. He has been looking at schematics he had and from Toyota for over 2 weeks now, trying to see why all these electrical circuits have in common... Geez... PLEASE, if you have any suggestions...I am WIDE OPEN!!! Thanks!

[@grizz5431]

Stating the obvious, at 10:00, my brain was screaming "You need to check the ground!". That's something I learned back in the late 70's with the advent of computer controlled fuel and ignition. Because some of the manufacturers attached ground wires in stooooopid places like thermostat housing bolts. But, good job. I'm surprised someone didn't catch it before it came to you.

[@deanb949]

Problem is today, the techs are too young to have been exposed to the daily run down to the last wire of systems they diagnose today. Back in the 80's the automakers were still (sadly) cutting their teeth on EFI and all the wiring logistics that goes with it. I got out the buiz in the mid 2000's and still take the "check all the basics" routine first and foremost while they're relying on the analyzer's leading them to component failure.

[@SchrodingersBox]

Dean, What do you mean “check all the basics”? If you have a P0171 lean condition on a v6 engine what are the basics you use over relying on “misleading analytics?”

[@deanb949]

@@SchrodingersBox As I've stated I haven't been in this field in well over a decade. When we had codes, we backed up immediately with a multimeter or our 4 ch. Fluke storage scope what the related component's parameters were. We didn't just jump at parts replacement. The meat of my comment was aimed at the chaos of 3 domestic and a plethora of imports all doing their own thing before OBDII standards were in place.

[@deanb949]

@@SchrodingersBox Didn't say the analytics were misleading. The techs took the data as a set in stone parts order.

[@SchrodingersBox]

Not sure I follow that. Data is just data, it’s not a direction and certainly not a conclusion on a part. I don’t see how that could happen. Maybe an example of your method vs a young tech method on my 0171 situation I described?

[@scottallen5269]

I failed auto shop in high school. In my twenties and thirties, I always took my vehicles to a mechanic for everything. At 46 I decided to learn about my truck and wanted to do everything myself. I’m 50 now, and I’ve changed my oil and filter, ignition coils, radiator, brakes, starter, wheel bearings, heater core, fuel filter and lines, wheel hubs,power steering pump👎(that one sucked) And other tune up type stuff. But this!!! This problem with truck has been a pain in my ass for so long I’ve called it a demon… like Christine. Truck would start, sometimes it wouldn’t, when running the electrical system did whatever the heck it wanted to. Always resetting the system, and having to put in the code for radio and security, sometimes the idle was perfect and sometimes there was a slight hesitation… once in a while it would choke out. Even having to push the gas above idle to keep it running and not be stranded. Then it would run perfectly for months… and I run my truck. I’m always off road, in the mud, 4x4 driving( even fixed it when the actuator wouldn’t engage) And pushing 75 down the gravel road in my 2001 Chevy Silverado 2500HD 8 cylinders pumping… and doing donuts around corners… … … then it cuts out at the stop light on The way home… 🤔 After missing work today and troubleshooting it with this time, I concluded it has to be a contact problem. I need one of those testers… man that would help. What I did was, because my truck would loose power completely trying to start it this time, I left the key to on position… and started wiggling wires. I wiggled enough wires I was loosing hope. That’s when I found this one wire under the motor… tucked neatly and hiding for protection… I think? I found that f&@)%#!!! Wire. But first I wanted to listen to a professional before getting ahead of myself. That’s when I saw this videos title. I’m soooooooo glad I did. You helped to answer the “why” and technical terms and how your breakdown/approach for this situation. The moment that you were at a loss, and nothing was making sense… thank you for that. I felt like an idiot because it took me so long to figure this out. Thank you for filling the voids so I can better understand what I’m doing. I’ll finish this book now. I felt damn good and I pumped my arms in the air too, when I figured it out. Not bad, for a journeyman Carpenter/craftsman, that failed auto shop. It was awesome what you pumped your arms in triumph!!! Sooooo cool

[@MagnumOpusSRT]

Excellent diagnosis. It seems many underestimate or overlook grounds. Your methodical approach is appreciated. Thank you

[@SchrodingersBox]

Yes even I overlooked it at first. in 9 years this is the first corroded ground I have ever run into.

[@willis6066]

I’m a Automotive Technician down in CO Springs. I really enjoy watching your channel. Thanks for all the awesome videos man.

[@SchrodingersBox]

Awesome!! Thanks for watching!! Love the springs!! Western Omelette my favorite breakfast place hahahaha

[@bchrisl1491]

Good clip. well done. Eric O had a similar case over on South Main Auto a month or so ago. turned out to be the ground strap between the motor and the firewall completely corroded away. BTY that connector is a called a ring connector, and that one is am “open barrel” design crimp. They take a special die to crimp, but they are better than the barrel type crimp electrically because they have more surface area between the crimp surface and the wire, reducing resistance of the crimp.

[@SchrodingersBox]

Hahaha I was trying to remember the name of the stupid connector lol!! Yes “Ring connector” was what I was looking for but my brain wasn’t working lol. Good to see you back again btw.

[@bchrisl1491]

@@SchrodingersBox I have shifted to working on marine diesel and boat issues these days. I was very pleased to see that a group of technicians wanted to see this clip as a learning device. I’m out there lurking most days.

[@jarrow708]

Just want to say thank you. I have a truck in the shop and it ran when it came in. I replaced the oil cooler lines on it. I went to start the truck and it was missing really bad. turn the truck off and would not start again. I did the same thing the other tech you talked about. I never thought about the ground. I bumped into your video late on a Friday. Just got in on monday morning and quick checked the injector pulse. It was working. checked the ground on the coils and there was nothing. Thanks for the help. I was really lost on this one.

[@SchrodingersBox]

glad to help!!

[@bernardaflores1720]

Great video. GM cars in the rust belt are known for electrical gremlins caused by bad grounds and grounding straps.

[@EileenHeitman]

Great demonstration and verbal communication. I’m 74, shade tree type, struggling to keep up with how stuff works. I’m a new subscriber. I also view South Main Auto and Rust belt Auto among a select view. Thanks Schrödinger Box!! I’m a builder/contractor so mine is a much simpler world . Dave in Omaha

[@simonilett998]

Hey Matt, love your work mate. I don't believe GM use the brown wire as a confirmation signal like Toyota etc. The brown wire in this design is a common low reference/ground internal to the PCM, shared by each coil igniter transistor, effectively it's a constant path to ground for all of the primary coil windings. The open ground you were chasing is of course the main ground for the secondary coil windings. However, the PCM may still be capable of monitoring this common primary/transistor ground for coil current/over current purposes, and maybe to detect misfires etc.👍

[@endurofan9854]

mornin sir, i lack knowledge in this, so i'm pretty curious, so that pattern ow wires on that coil means 2 grounds? one for primary leading to PCM and one for secondary leading tothe battery - terminal/body, and one positive from the battery and one positive fron the PCM aa the trigger for cut-off on primary... did i get it right?

[@simonilett998]

@@endurofan9854 Yep, pretty much spot on mate. One pin (pin D) is a shared positive supply fed via a fuse (one fuse for odd bank, and another fuse for even bank) to power the primary coil and internal coil pack electronics. One pin (pin C) is a square wave switched input from the PCM controlling the primary coil transistor. One pin (pin A) is a shared constant chassis/battery ground, probably for the primary coil transistor to switch to. The last pin (pin B) is a shared constant ground, grounded within the PCM, probably for the internal coil pack electronics to ground to, and maybe the PCM can also monitor this wire for self diagnosis functions etc. Pin A and pin B may actually serve oposite functions to what I've stated above but I'm not 100% sure, but I can confirm they are both constant grounds and can be tested as such. Hope this helps👍🇦🇺

[@SchrodingersBox]

@endurofan9854 correct.

[@agold3765]

I had the exact same problem on a Jeep Grand Cherokee. The mechanic, before I purchased the vehicle, worked on it off and on from October to February and couldn't fix it. I stopped and asked about it and he offered it to me CHEAP because he couldn't get it running. I purchased it, had it towed home and a few days later started to investigate. I saw where and what he was working on and went right to the wiring schematic to see what was common to the problem area. It turned out to be an open connection back to the PCM for the engine sensor(s). I opened the first place where the factory spliced the wiring and hooked a jumper wire to it and back probed it to the PCM. Vehicle started right up. Success.

[@GreatDataVideos]

Thank you for taking the time to methodically teach us, as you always do.

[@SchrodingersBox]

My pleasure!

[@jazzstarish4186]

Greetings. I have a 2005 Chevy Zafira 1.8. No spark with new coil. The ignition coil connecter (5 wires 4 go to each one). The 5v reference on each on is around 4 volts. Does it have to have 5v to spark? Can I take a test light on positive battery and supply it to one to spark? 12v is too much. Thank you.

[@SchrodingersBox]

You could do that yes. but there also needs to be a 12V on one of the wires. has to be.

[@glennmiller5451]

@@jazzstarish4186 loop l.

[@timothymielko983]

I commend this guy for his ability to diagnose and articulate the issues clearly. He makes it easy to understand how the system functions and how to diagnose what to look for and where in the system. Excellent communication skills! I would love to know what scanner system he is using for this video.

[@SchrodingersBox]

Thanka so much. in this video i used an Autel MS909 scanner.

[@abdul-kabiralegbe5660]

Great video! I read (see bottom) that the Low Reference on those ignition coils was an ECM sourced ground which is a dedicated ground for the coil electronics. The chassis ground is meant to supply a ground for the actual coil windings, but can supply the coil electronics too if the Low Ref is down. This system contrasts with Toyota's 4 wire ignition coil where the fourth wire is the ignition confirmation signal (IGF) telling the ECM that the coil fired. Source: There's a PDF titled "Coil on plug ignition - the wired differences" by Matt Dixon which explains this and more. A quick internet search will show this PDF in its result.

[@ChipperTheChipster]

No one thanked you for this wonderful source of awesome information!!!

[@abdul-kabiralegbe5660]

@@ChipperTheChipster Thanks!😊

[@timduvall6488]

That was awesome. My Challenger cutout i pulled over and the starter was still turning over. I swapped a couple relays. Didn't help. But also when I let off the key fob starter still turning over. It's been in the shop for four days. Still haven't heard anything but it's got gremlins lol. I'm retired plant electrician. Electronics degree but that was first time I saw the explanation of electronic ecm diagram and grnd. Diagrams. It makes me want to take a class. Thnks

[@Ravenshadowson]

Love your videos. I learn so much from your videos

[@minamcconnell9932]

Absolutely the most in depth video we have seen for problem solving a vehicle. We are definitely going to check our ground wires and see if our vehicle will start. Definitely got us as new subscribers. GREAT JOB!!!

[@SchrodingersBox]

Glad to hear. Just check for an open ground first. It will save a ton of time.

[@minamcconnell9932]

Will do tomorrow. We changed every sensor already and still crank no start😵‍💫 🤞 it's a ground. Will let you know how it goes. Best UTuber that we ever watched! Subscriber for life!

[@Kaunas-rx3qv]

Great work Matt. Thanks so much for another excellent diagnosis.

[@xj31]

How easy it is to overlook the basics. Seems like whoever looked at it before you could not see the forest because of all the trees. Good no nonsense common sense diag there, thanks for sharing

[@randybeard6040]

I use to work with a guy that had a IQ off the Chart, he had Total Recall on everything he read, could resite a Dictionary and carve a Gun stock from a 2x6. This guy could make a couple checks on your engine and tell you what was wrong. I had a recently overhauled engine in my car-one night when we got off from work at 12 midnight, temp/ about 10 degrees, my car would not start, only turn over, he instantly told me that it had jumped Time, I told him that it was just overhauled several months ago-he said well they didn't replace the Timing Chain so he just advanced the plug wires on distributor and engine fired up as it should. He said now go back to the guy that overhauled your engine and tell /ask him why he didn't replace Timing Chain, of course guy denied that he left old chain on my car...

[@KWAHU93]

@user-pl1uj5ks4mgoogle advancing a distributor.

[@SuperReznative]

@user-pl1uj5ks4m hah , that the difference experience "brings to the table ". I understood the very thing he was describing about the timing/ plug, ..and it also took me back 30 years when I had to tow a car ,home from far away, because of that that issue. Time jumped.

[@stephenrose8188]

Excellent video and another example of how important it is to go back to first principles on such difficult to find faults. I'm in the UK and wanted to say 'thanks' for a great video session.

[@SchrodingersBox]

Thanks for taking time to write!

[@mechanic_marky]

Nice find. I also love being able to fix problems that multiple others were unable to find. Keep it simple.

[@SchrodingersBox]

That's the plan!

[@8307c4]

Wow... I have a 1995 Volvo 850 with this crank no start issue... I think I will follow your set of steps in the diagnostic, that was pretty incredible.

[@SchrodingersBox]

it works every time!

[@carlm2590]

Because you helped the poor with their auto repair I thumbs up every video you publish. God bless you. 👍 and I’ll subscribe to your pay content.

[@SchrodingersBox]

Thank you!! yes I have done a lot of free work lately including this one.

[@kennethkaiser7370]

it took 21 minutes and 5 seconds to realize WTF my issue is. Thanks for the info! I pretty much fried my starter and wasted some (to much) time, but this hopefully solves the issue **2009 Ford Escape 3.0L**

[@johnshinski2994]

An absolutely great lesson. Thanks

[@Briandutoit-sl2nd]

Thanks my man great lesson

[@keland2002]

Thanks so much! I had the exact same problem on my 2004 Chevy silverado. After watching your video, i was able to troubleshoot and fix the problem. The truck now runs like new. Now, off to the next project, a drivers seat rear motor that won't go up or down. Wish me luck 😊

[@DANNYN224]

Great diagnostic and love learning from you

[@SchrodingersBox]

Glad to hear it!

[@fredsalter1915]

Great vid, sir. I wonder why a DTC wasn't set for the coil failing to fire. Thanks for posting this vid for free!

[@SchrodingersBox]

Yes I got asked that a lot. The reason is the brown wire that sends a validation of coil ignition only functions when engine is running. It doesn’t function during cranking. Because this was a crank no start that validation was never a factor so therefore no check engine light.

[@fredsalter1915]

@@SchrodingersBox Thanks for responding. But you said that the customer concern was that the symptom gradually become worse to the point where the engine would crank but fail to catch and run. I blame the ECU for not being smart enough to detect a faulty ignition circuit. Rock on, S.B.!!!!!! Love your vids!!!

[@SchrodingersBox]

Yep the reason still applies. The issue was with cranking the engine and it not starting. It would happen more and more frequently. When the engine wouldn’t start you won’t get a code for the reasons mentioned. When the engine finally starts you won’t get a code either because now it’s running.

[@JohnSmith-pb1dd]

Thank you, amazing video, you are a great teacher 👏

[@SchrodingersBox]

Glad you think so!

[@embreesmith7613]

Bernie !! Glad You came by today Say hello to Ms Vikki and the Kat

[@kartamap]

The Disgruntled Mechanic-subscribed !

[@TheDisgruntledMechanic]

TY!

[@tonyb1968]

Oh connector? Funny name for a ring terminal. Lol, just giving you a hard time. Great diagnosis, practically no parts required. The parts cannon would never have fixed that one. The owners best decision was bringing it to you. Thanks for posting this one 👍🏻

[@SchrodingersBox]

Hahahaha dammit my brain just totally couldn’t recall the name of the stupid connector and of course I thought of it afterwards but it was killing me knowing you guys would surely point that out lol!!!

[@1yotube]

I have watched 1000 and 1000 of videos about this issue !!! and I can tell you did a good Job. You have tugth me farther than the the técnical aspect of the subject.

[@AlexLopez-q6u]

Nothing beats a good vehicle like a bad ground !!!!!! Thank you for taking the time to do this .......

[@brandonslater2987]

I live in Denver and spent a good 6 months on and off troubleshooting a no start exactly like this one. When I started I knew nothing. I have spent a multitude of hours learning wiring, signal wires,5 volt square waves, etc.. I have finally narrowed it down to my coils not firing. I bet its a ground issue now that I see this video. Or a control issue. Unless you need a car for your next video I am happy to tow it to you.

[@SchrodingersBox]

I’ll take it!!! Email me at [e-mail].

[@cdawg9149]

Remember the late 60,s and 70;s v8 motors that were so basic. Now you have to be a mini Einstein to diagnose cars.

[@SchrodingersBox]

I also remember in the 70’s and 80’s that a car seldom made it to 100,000 miles. Now the first tune up is due at that time. No airbags. No antilock brakes. No vehicle stability. No navigation. Good mileage was like 14MPG. Emissions were over 50 times higher than now. Anytime the weather got unusually cold you had to put starter fluid down the carburetor hahahahah. The technology has made cars way way way better and far more reliable.

[@724Drizz]

After my vehicle being down almost a month , towed to 2/3 mechanics and nobody can find the problem till we came across your video. You Explained everything well, thank you. What gauge ground wire would you use to repair this

[@SchrodingersBox]

Recommend a standard ground strap- more corrosion resistance for the location.

[@duanedonaldson2262]

Constructive response brother. An observation here today and with many many techs, you don't follow your own written procedures, you get distracted trying not to waste a step because others expect you to not waste time checking something that ought to be ok. You went for spark, no spark, you moved over to the injector control and it's ok, then you moved back to spark. Please follow your own set of rules, we must work like robots, if we waste a step in the spark diagnosis, at least that step in our own process has been covered and verified. Performing a bypass test is an accepted procedure and has proven to be the proper diagnosis in this case but you should have been there some time ago right after the no spark test and no need for the injector control test until you are completed with the no spark diagnosis. I really appreciate the test light DIY diag but for those who have 4 channel scopes and who know how to use it, all 4 wires would have been tapped back at the spark test process and the problem was found, your process should have come to the same conclusion during the same no spark process, check powers and GROUNDS (LOL), we do this all the time without fail (except today). You pulled your ground probe and instantly regretted it knowing you can do a ground bypass test, why, because you don't have a checklist/process that you follow in front of you, off-camera. Too often we rely on our poor memories under stress and make our supposedly proven process fall to pieces on video. The moral of the story, stick to a proven process without deviation & don't poison your own well brother. In history, this is a bad ground quite often. Thank you for the case study and the extended whiteboard lesson. Love your channel. Appreciate that you know what you deviated from.

[@SchrodingersBox]

Well it’s a whole different thing when filming. You are thinking about the camera angle, are you blocking the shot, is the audio on…… and also I admit I was kind of fixated on the crank sensor. so it’s not like in the video when you just go in sequence in a flow. you check power. then you look back at the video and make sure you got the shot. then you go back and you forget you never tested the ground because you want to look at the next possibility in your list especially since I was thinking crank sensor just from the customer info. had I not had “crank sensor on the brain” and/or wasn’t filming I would have done exactly as I did in the video but would have checked ground right after power and that would be the end of it. I would know the common ground was open based on my knowledge of the circuit design and probably 10 minutes diagnostic time max.

[@rodbeaty6704]

i yelled at the screen when you checked for 12v input and skipped streight to signal checking lol great video my brother

[@bob8776]

You’re so right about the poisoned well. It’s been my experience that whenever there’s a general consensus about what the problem is yet the vehicle still isn’t working, it’s because everyone is wrong or don’t have any idea what they’re talking about. Go through the process of eliminating potential issues yourself and zero in on the real problem. You’ll waste less time and money and you’ll actually fix the thing. I literally just picked up a 96 Chevy for dirt cheap because it didn’t run. Guy said it was the fuel pump and had a couple other guys tell him it was as well. Ten minutes and an $18 coolant temperature sensor later I was driving away in a truck that runs great and is in pretty decent condition

[@miked1372]

Thanx! I had a no spark issue but ground ohm test was good. I checked my G102 anyway and sure enough it fell off with little effort. Corroded. It was dropping out soon as I cranked it, weak ground. Ran new ground and all good. Thanks for this. It was making me nuts

[@benniedonald]

I truly appreciate this video. I have a 98 dodge ram 1500 5.2. "Stop laughing" 😅 My starter burned up and now. I have this problem unfortunately I knew it had a parasitic draw. I eliminated all of them. At least I thought I had. Most of it was due to a poorly done radio installation. Watching this helps me understand the ground is probably the culprit all this time. Or at least gives me an idea what to look for. Thanks again for the troubleshooting tips. 🎉

[@SchrodingersBox]

Excellent!!! You are approaching it correctly for sure. You'll get it soon and its so satisfying when you solve it!

[@danpowell5286]

Totally glad you left this one up, I’ve got an 06 f150 CNS that nobody has been able to diagnose, I think you’ve got it. I’ll let you know.

[@dbayboyds409]

Thank you so very much for taking the time to explain your process! I never knew the value of a test light. Thank you from Australia! It’s got me thinking. If that system had 2 grounds shown on the diagram how come the second ground didn’t take the load? Are they broken at both spots?

[@Lambros_Stefaneas]

probably, this car has only the one ground. it will be kind of a different model/engine etc.i

[@SchrodingersBox]

Thanks for watching! As Lambros indicated, it’s one ground. the firewall ground is for the 4.3L which has that ground but not the block ground in the video.

[@Lambros_Stefaneas]

@@SchrodingersBox Thanks man, for all the awesome videos that you are sharing with us.soon ,I will come and be part of the Q-group 😀

[@mynyasabut]

This is generally cause most technicians think in terms of 12v plus, ignoring ground issues or get lost thinking obout sensors, your aproach is more efficient i loved this video, i work audio systems and a client mentioned a problem with his engine, it turns out another mechanic forgot to reconnect the physical batery ground so the car was taking ground though the engine block wow! i just recconected it and voila! the engine problem went away when other 3 shops couldn't find the problem

[@DirtyWorm12]

That's the problem with automotive technicians, there are a lot or there that "can diagnose" but are really just code readers/parts changers. You gotta let the data drive your diagnosis and you gotta understand the fundamentals of electrical and you will diagnose anything. Great diagnostic, I can't stand it when I let the well get poisoned, ,gotta step back, delete and reaet

[@wyattoneable]

Nice sweat shirt. Mike is a great guy. I smiled when it started. Following a path of solid diagnostics wins every time. Great video Matt.

[@SchrodingersBox]

Couldn't agree more- he is a class act and the sweatshirt is quite comfy hahaha. I wear it whenever I have to crawl under a car in the snowy weather so I don’t ruin my Schrodingers Box sweatshirt hahaha

[@richardbizzoco624]

great job. i just went thru a full-on diagnosis (crank-->no start) where current was interrupted and there are so many possible things it coud be. Mine was an older car with a ripped out alarm system and many cut wires. Ultimately it turned out to be an EFI relay that worked, but did not transfer current from pin 87 to 30 and replacing the relay brrought back the check engine light, which did not light up with key on. So solved. interesting and well done video.

[@BellaRocko]

You are an amazing teacher and diagnostician! You fix cars by THINKING! Thank you thank you thank you for sharing!!!

[@SchrodingersBox]

Wow, thank you!

[@frankthomas2231]

Great diagnostic. I have a 2010 Silverado 5.3l with a similar issue, except I have a P0340 code. Ive checked wire integrity for the CMP and all is good, replaced CMP, still no start. Spent my whole Sunday trying to figure it out. This evening I`m going to go for fuel and fire. I have crank signal, but not CMP signal on scan tool. Thanks for this video. It gives me another direction to go with my diag.

[@SchrodingersBox]

yes on ANY crank no start I always follow my FASTEC method and it never fails to ultimately find the issue. It is weird though your signal integrity was good on a 0340. what was the reference and signal voltage showing when you tested it?

[@frankthomas2231]

@@SchrodingersBox reference was 5v. I don’t have a scope so I checked signal with multimeter, showed .150v- .20v while cranking. I’ve got a scope ordered, will have Wednesday, so I’m going to check it and get a waveform to see what it looks like.

[@SchrodingersBox]

You don’t need a scope you just need a basic DVom. Of course the reference is 5V- what’s the signal voltage showing when you ground it?

[@frankthomas2231]

@@SchrodingersBox I’ll have to check that. I was hoping to work on it this evening, but didn’t have time. I did do a quick fuel system check with a shot of starting fluid, still didn’t start. I did notice it try to fire one time while I was cranking it. A little background when it started to act up. I do a lot of towing with it. The last week or so I noticed an intermittent loss of power, especially while going up a hill. I did a full health scan Saturday morning to see if there were any pending codes that hasn’t tripped CEL, and only codes I had were for TPMS, which haven’t worked since I’ve had the truck. Saturday afternoon I went to the store and it was running fine except for a short loss of power one time. I shut truck off at the store, came out five minutes later and no start. Checked codes and had the P0340.

[@frankthomas2231]

@@SchrodingersBox I’ve got 5v on signal. I checked at the sensor and ECM. I checked for fire. Nothing on signal wires at the coils I also just tried another CMP sensor just to be sure I didn’t get a bad one. CKP sensor shows about 180rpm when cranking but CMP shows 0 and also 0 on counter. I don’t have access to my alldata at home so Ive got to go to shop to look everything up. Going there now to get diag procedure for the coils.

[@MRWALLEYZ]

Thx very much for this..I heard "intermittent" at first...that clue made sense as well...now back to my son's 2008 Altima with a new alternator that is not charging the battery...wonderful...

[@angrypop2594]

I recently went through this exact problem and after spending over $800.00 I finally took it to someone who fixed it in a few minutes. The ground was on the back of the motor that wasn't on the diagram.

[@SchrodingersBox]

Sounds like they know what they are doing!! Even if ground wasn’t on the diagram they would probably have just made a new one- kind of like I demonstrated showing the ground would fix the car before I located it.

[@stephencrawford7641]

This sounds rather grand…..it’s not meant to. I bought a Bentley for peanuts, because crank no start. Everyone and his dog has tried before me…. Using your techniques I’m getting closer to solving the issue. But much more importantly, I now have the CONFIDENCE to solve the problem. Like most “enthusiasts” , the electrics must be be the most dreaded. With my £5 checklight, my one way buzzer, and my multimeter along with my new found CONFIDENCE … I’m ready. And yes, your right, when you solve it the feeling is often greater than the driving… I’m an accountant, and I can tell you I get more satisfaction getting something working than I ever did double entry book keeping - although, it pays better! Who needs golf?

[@jackwill3578]

AN OLD MECHANIC ONCE TOLD ME "ALWAYS CHECK YOUR EARTH WIRE" !!!!!!!!!!!!!!!

[@MasJets]

Great video, and your ignition video is 1 off the best I’ve ever seen really nice explanation , and the most important think is the way you explain, it is so clear and understanding , you do put 100% effort to make sure others understand.

[@SchrodingersBox]

Thank you very much!

[@StoneKathryn]

Take a bow!!!! Great diagnosis. I liked seeing this. Thanks. One guy I watched thought it was the cam sensor because when he tried to start the engine the rpms needle didn't move. It did turn out to be the cam shaft sensor for him. It didn't look like the rpm needle moved for your situation but did it move when you fixed the ground? Just curious?

[@SchrodingersBox]

Yes it did. Lots of cars do not show a tach movement during cranking - it’s a sensitivity thing. But you will see RPMs on a scantool on all cars which is a more reliable metric for sensor operation.

[@LinoHart-fr2mj]

I have watched a couple of your videos and not only learned a few things but also entertained. Thank you

[@SchrodingersBox]

Thank you! I try to keep it fun.

[@eduardoalba3012]

Man you’re amazing at what you do u make it look so easy and the way you explain things is at another level man ! God bless you and thank you!

[@SchrodingersBox]

I appreciate that! Thanks for commenting!

[@grenvillephillips6998]

Great to share in Matt's total chuffedness - I always enjoy a happy ending!

[@SchrodingersBox]

That sounds dirty lol

[@grenvillephillips6998]

@@SchrodingersBox To be chuffed is a British expression meaning delighted. I wasn't sure whether it was used in common parlance in the bars of Benson, Arizona. But soon maybe?

[@deltabloo]

I am patting myself on the back I had this figured out before you! Always check the basics first! Years ago my friends Chevy Citation would die and all the lights would go out. I looked under the dash and found a common ground that was loose. He thought I was a great mechanic! (I’m not😮)

[@SchrodingersBox]

Pretty impressive- so how did you rule out that it had to be a ground as opposed to a a crankshaft position sensor problem that soon?

[@deltabloo]

@@SchrodingersBox when I saw that you had power to all the places it had to be, it made sense. Electricity is simple. I am an overhead lineman and we know that if we don’t have good grounds , we have issues. Electricity just wants to complete the circuit. You had power to coil packs and injectors, but it wasn’t flowing through, ergo, bad ground. I’m not pretending to know a lot about this, I was raised on old school points and carbs but your deductive path was right on. If something doesn’t work, make sure it’s plugged in. If it’s plugged in, then why isn’t the current flowing? Thanks for the video. I’m presently installing an LS in an older car so the more I learn the better.

[@JR-bj3uf]

Thanks for the fantastic video! Here is the part that sucks. The customers say "you just replaced a wire end, that wasn't hard!"

[@SchrodingersBox]

Hahahaha so true!! hell the VIEWERS often say that and tell me how much faster they would have done it LOL!!! when you think about it - there are never any hard electrical repairs. The repairs will always be easy. it’s going to be either an open, a short or a high resistance. that’s it- one of the three, every time. all are easy to fix. but find which it is and more importantly where it is can take hours and hours.

[@JR-bj3uf]

@@SchrodingersBox Back, many years ago, when I did this kind of thing for a living, we had a flat three hour shop rate fee for any electrical work or short and we NEVER let the customer watch.

[@SchrodingersBox]

it’s good advice in general lol but I agree. if customer watches they are going to say “well why didn’t you look there first you incompetent monkey? You should just charge for 15 minutes!” and then they will go on KZbin and tell how much faster they would fix whatever they watch there too lol!!

[@JR-bj3uf]

@@SchrodingersBox I really liked your presentation. Gounds (or the lack of them) can be a real nightmare. It also gives credence to discovering the actual problem rather then throwing parts at it.

[@skoff1214]

Im into the same issue, crank but hard starting at cold start. thank you for this content and i will try this as reference.

[@raycook1503]

Such an awesome video. Shows that other areas can cause problems thatcwere never thought about. Also some ignition systems are hot at all times, and the ground is turned off/on to fire coils and injectors as needed.

[@DanielDebord-v8w]

I have a 2002 Chevy trailblazer. It just died. All of a sudden I change the fuel pump fuel filter, coil, packs spark plugs starter oxygen sensor fuel regulator, still cranks no start I am I just don’t know what it could be

[@SchrodingersBox]

What data do you have?

[@Ben111778]

This was a great video! I appreciate the detail you go into, it provokes a great amount of thought with revealing connections so that in turn, I could figure out that I'm having back emf issues with my 73 Mopar 360 causing the plugs not to spark and am missing an engine to chasis ground on the tranny end of the engine!!! I think you just solved me a whole number of intermittent electrical issues I've been having! Thank you!

[@gt3tunecl725]

Great video. Only i have a Question. Why you Can use a positive pulse for actívate the coil and why and why is it not a negative pulse. I want to learn a little bit . Thanks for sharing your knowledge Teacher

[@SchrodingersBox]

Great question. You have to look at the type of transistor. If it’s a PnP transistor you use a positive. An NPN you provide ground. I can tell you I very very rarely see NPN on any signals for coils.

[@gt3tunecl725]

@@SchrodingersBox omggg thanks for sharing that little secret. The electronic and electric is awesome. Greats for Chile!

[@oliverthemechanic8532]

Mate very nice video 😉 help me a lot 😉 just want to ask where you get your wiring diagram for a different brand of car? Thanks in advance for the reply 😉

[@SchrodingersBox]

Normally I google them but if I can’t find one I use Mitchell DIY