How to test an ignition coil/module with a test light (distributor ignition) - GM

[@mikethompson660]

As a mechanic myself for about 50 years I can’t remember everything but that was the information I needed to fix the truck I needed to fix. Thank you.

[@scottwitkowski1298]

It's videos like these that confirm I'm not a mechanic. I'm a parts changer.

[@tajhealthnature8570]

😂😂😂

[@daraprak6498]

Literally how I feel Everytime I’m watching a scanner dan video 😩😩

[@mikeneff832]

Best part is this is one of those iykyk things. I’m here from a forum and this is very forum

[@JamesDoylesGarage]

Great Job! You should take a lot of pride in how careful you are to teach us all so well. I really appreciate you and your channel.

[@brandonmajcher3273]

Thank you scanner Danner I know this video is old but it just helped me school my hard headed boss on a truck with a messed up pickup causing a no spark no injector pulse situation. Don't get to deal with this old school stuff often but it helps to have the videos and know come of the basics.

[@sunray0162]

Thank you for your video, my truck broke down on the highway on my way to work, fuel pump worked so I didn't know what check first until I saw your video. You explained everything very well. You saved me a lot of trouble shooting time. Thank you.

[@TubeInspire]

Same thing happened to me in the weekend 😅 here for the same reason, this guy has good videos

[@thesetruths1404]

Thanks man this was a great help! Got a free 91 Chevy 5.7 truck (366,000 miles) and I think the only issue may be the ignition coil as I've checked all other main elements plus the spark wires (no spark from at least one of them).

[@trentrichard2871]

Thank you for info. Have 91 camaro conv that ran great than after not being used often it would not want to start next time started and ran fine now it does not have spark on no 1. You helped me save alot of time

[@wilsonvalentin1738]

On a 98 witch pin from the ECU goes to the coil

[@davidreynolds4684]

Good video as usual. I've got a 1990 f150 4.9 liter recently replaced the front tank fuel pump was running good with the slightest miss. Had planned on fuel injection flush. Last week no start. Checked fuel at relief valve shot out strong. Shot starter fluid and fired up. Drove fine. Stopped and started several times. Next day friend brings it home from work and said when he pulled in the driveway put it in park and a few mins later it died. Tested spark on #plug wire with plug in light tester. Sparked 1 time when first cranking then nothing. Tried Next wire. Same thing. 1 spark -nothing. Did this on 4 wires. Checked volts on coil leads. Constant hot with key on one side. Pulse on one terminal when cranking. Used test light on coil to dist cap got steady pulse. No spark from dist to plug. Found bad bulb in tester. Used spark plug I wire grounded to valve cover bolt. No spark.Rotor cap dist cap plug wires and plugs are a few mo the old. Look good on terminals. Rotor turns on dist. Held the rotor to see if the shaft would slip if under stress. Twisted right out of my hand No play in the shaft up down or side to side. The haynes manuals have actually gotten more useless . They don't cover diagnosing anything. It's all remove and replace parts. Even with the fuel pump getting weak where it wouldn't run I've never seen a check engine light throw a code. It does light when starting but never lit when truck was running so bad it barely idled. Any tips on where to start again would be greatly appreciated.

[@ScannerDanner]

This video will be more useful on your system kzbin.info/www/bejne/op28d3d5apKml5I Let me know what you find.

[@davidreynolds4684]

@@ScannerDanner thanks so much. I wish you were down south. We could keep you busy. I can't do it all anymore.

[@ascaniboy]

I missed the explanation of what or how the pulsing occurs without the distributor interrupting the circuit. Is the PCM/ECM pulse driving the coil ground?

[@david_bmx1148]

Hey Dan quick question I have 1999 S10 cranks no spark condition I tried everything spark related I put in used computer it fired up seemed like a wire was off now I tried again no spark again??? Any ideas??thanks alot

[@shelbycobra1401]

I had a 96 Chevy 1500 truck 4x4 5.7 V-8... crank no start it would kind of shudder or slightly start but not run smooth then just crank but would not start. Replaced the cap and rotor along with ignition coil pack and it started right up and runs great now. I didn't just throw parts at it though i did about 2 hours of checking fuel pump, fuel relay, pressure at fuel rail and it all checked out. Next tested spark it was there but faint or weak not much flash in my tool tester. Pulled the cap and rotor and had a burn hole in the rotor so I knew I was on the right track. Replaced ignition coil and cap and rotor and its fixed. Hope this helps someone with my symptoms!!

[@tinytim9453]

Thank you, my truck has the same symptoms as you described, fuel is good, spark somewhat ok but no start. Gonna check those other things.

[@sayarkhan1744]

My name is sayar Khan from Pakistan I am auto cars electrician I solve your problem 03329028717

[@paulfiebke3909]

Watch it for a 2nd time and forgot this one your the best keep up the good work ❤

[@worteldrie4980]

You really did all of this BY THE BOOK. Read all of this in my manual. But its good to see it in practice, Thank You!

[@ScannerDanner]

They are my techniques, so it would make sense that, that is whats in my book. Nice to see you recognize that! Thank you!!

[@worteldrie4980]

@@ScannerDanner Even better. Subbed

[@shelbycobra1401]

Also when replacing the coil pack it has two pins pressed in to hold it to the bracket instead of drilling I used two good punches and was able to punch the pins right out in one or two minutes instead of drilling it out. I spray it with PB Blaster or WD-40 and then start the punch and give it another quick spray half way through and the pins will just start to fall apart and it'll come right out of the bracket. I did have a drill ready if I needed it but the punch and a hammer did the trick. Just a tip to anyone looking for ways to get those "rivet pins" out. Good Luck.

[@olenaerhardt7725]

Thank you for the film. Pls could't you tell where is the Ignition Control Module is located on 2001 Saturn SL2. Also I removed one on 2003 Chevrolet Cavalier and there is some red stuff on the small mounting bolts for that module. Could it be the red thread locker?

[@slammedb18a1]

So at 1:21 those two plugs that go into the coil, my yellow wire the plug is not plugged into anything? I cannot find anything remotely close that it would plug into does anybody know if that is just a ground or is it something else? Got to get this thing running again

[@donaldsmith4542]

Is there a fused ground that comes out of the coil bolted to the motor below the coil

[@greggwest2551]

I wonder if an analog meter like the Simpson 260 would provide enough load (through the meter movement) on the coil secondary to accurately perform the secondary resistance test.

[@PSmolchek]

What is the aligator clip portion of the test light connected to? POS battery or NEG battery or grounded to frame? THANKS.

[@ScannerDanner]

Negative

[@ScannerDanner]

Any known good ground

[@edwinendaya2967]

Sir good pm I'm edwin from Philippines I have problem car hyundai elantra 1996 model I replace new ignition coil new camshaft but still doesn't start can I help me how to diagnose the problem thanks

[@ScannerDanner]

post this to my forum www.scannerdanner.com we can help you there and it is free to join.

[@Trucker-Belly]

When you tested the coil control (white) was your test light on ground or 12v? Also, what of there wasnt any control signal? What would be next?

[@billsmith2212]

That looks like a GM HEI / TBI system . I guess those injectors don't go into clear flood mode with the pedal on the floor . That's why you unplugged them . Great lesson .

[@MSoloWacck]

Hi i have a vw golf mk2 gti, it dies when driving, shakes a lot and seems like it has lost its power quite a bit and the headlights are diming at night. Culd it be the ignition coil?

[@matthew53690]

Did you have your test light hooked to ground when testing both coil + & - or did you switch to (B) + when testing coil -?

[@ScannerDanner]

test light to ground for both tests

[@ScannerDanner]

Just in case of an inadvertent air gap and subsequent spark occurring at the battery. Safety is all. Don't want to blow up the battery

[@davidl5121]

@@ScannerDanner New cam/crank sensors with 12v & ground to the connections.. new coil doesn't throw any spark, what could be the problem?

[@XtremeSportX247]

I have a 2004 Grand Prix GT with 276,921 miles. I have bought it brand new and have bought other cars but I used it for short-distance traveling. Nothing major has happened to it over years besides normal preventative maintenance issues. However the last few yrs have been the most active on replacing parts. I have had to replace my ac resistor module 5 times, blower motor wheel 4 times and the water pump 4 times. Most recently I had to use JB weld to fix a cracked radiator because apparently the fans wasn't turning on correctly and I have a coolant leak somewhere. That caused the car to run hot with must affected the small crack in the radiator. In the past week, I have noticed the car not starting until the 3rd turn or when i press the gas pedal. It started only doing it in the mornings and would be fine throughout the day. Now it does it every morning and all day. I have heard things like cleaning the Mass Air Flow, replacing Fuel Filter, replacing Crack Sensor, replacing Air Filter, Tune Up (which I did already), Relays, Ignition Switch, Starter the Cam Sensor. I have kept my car up to date with parts but I just dont want to go buying all these parts for nothing. Does anyone have some advice or similar concerns on their 3800 engine or grand prix. (please help)

[@charlesdowns1691]

i have a 2002 grand prix but with 3.1 engine. it would overheat alot - mainly in hot weather' but really anytime+i had my coolant temp sensor changed and it stopped the overheating issue. i think the cts also controls fans too. have you changed this sensor? also have you checked fuel pressure regulator. if bad the vacume line to it may have fuel inside. i ran vacume gadge into my car from a long vacume hose attached to manifold. 3.8 may have one built inside+ those are helpful also when you study the needle. clean injectors and all sensors possible+ i wipe m.a.f. hot wire with alcohol pad gently and spray screen. check map sensor is my next task +i read it can cause starting issues. im gonna have mechanic do it cause ive read if changed map sensor other things need changed and ive not studied it enough to be comfortable. use correct octane for gas. also i use startron fuel treatment -ethanol neutralizer- it helps mine start faster or it says? also cold start issue can be~ battery~fuel injectors leaking or fuel system issues. check battery connections for corrosion and tightness espessially negative post. check +clean throttle plate. clean pvc valve. just basic stuff that youve probably allready done. i just like these cars and learning on them. i changed my plugs+wires. ac delco irridium are best plugs.+ but 3800 v6 supercharged ( code 1) will use ngk type ptr4b-15* ( gap .060")

[@charlesdowns1691]

i would do a check on engine if it has overheated much for cracked head or gaskets+ just to be safe.

[@XtremeSportX247]

@@charlesdowns1691 thanks but I gave that car away in 2017. Driving a Toyota now. Havent been to a repair shop or auto part store in 5 yrs...

[@Ken-1]

What if you have coil negative control, and feed voltage, BUT new coil still does not spark? Currently dealing with this. Injectors fire, cam and crank signals good, coil control activity confirmed (with test light only), but still no spark. This one's throwing me for a loop! (2000 Dodge Ram)

[@ScannerDanner]

If you have confirmed coil control and you still have no spark, there are only two possibilities. 1. You have a bad new coil (not uncommon these days) 2. You have control, but the computer/module is not grounding the coil long enough to saturate the coil. This usually results in very very weak spark that looks like no spark unless you close your air gap to less than a 1/4". I have seen this a few times with ignition modules but never with a Dodge where the ECM IS the module. Are you sure that you are maintaining battery voltage on coil positive during cranking?? Here is a video where we had the issue I am describing kzbin.info/www/bejne/m6DSlXyMfMx6r9k

[@Ken-1]

@@ScannerDanner Thanks for the speedy reply Paul! You're amazing! -- Battery voltage dropped a bit during cranking but not lower than 11.5 or so if I remember correctly. I've no longer access to the car, as the owner is getting it towed to a shop now. BUT, it dawned on me that I still had the old coil on hand. Gave it switched power and ground with my power probe and it sparks!!!! It's a good blue spark too. Confirms the old coil was not bad, but is this good enough evidence to warrant a PCM swap, in your professional opinion? Interested to see what the shop does. I'll keep this thread updated

[@sandiegojody]

Hello, so it seems like i have no coil negative on the white wire on my 94 Chevy Blazer 5.7. Can i just directly ground the white wire?

[@ScannerDanner]

no you cannot, that will not produce a clean enough signal. Do you have injector pulse?

[@jeepguymb45]

Thank you. Can u show the corvette ICM diagnostic while it’s off the vehicle? It appears mine heats up a great deal and I want to verify it’s bad

[@ScannerDanner]

The off vehicle tests aren't good imo. The load on them is not the same. Here, watch this one kzbin.info/www/bejne/sIaro42Krb51fac

[@kennethlee4195]

I have a 93 f150 4.9L inline 6 cylinder it starts great then i drive it for like 5 minutes and it feels like its running out of gas i turn the key off and start it and it runs great again for 5 or ten minutes any idea what it could be

[@ScannerDanner]

You'll need to do some tests, fuel pressure, trouble codes? Can't help otherwise

[@kennethlee4195]

How do i get trouble codes on a 92 ford f150 autozone couldnt do it

[@soptea]

I love seeing a scope in action ,thanks for video !

[@DeceptiveD2]

I have a 95 jeep grand cherokee 4.0 where i had power to my ignition coil and no ground on my driver wire. Any advise would be appreciated.

[@roscoeferguson3829]

Great video, helped me to diagnose the problem with my nieces truck. I have a question, would it be safe to use an oscilloscope to check for control signal? Thanks . . .

[@ScannerDanner]

Depends on your scope. Primary ignition coils can produce upwards of 400v when the field collapses

[@ozzstars_cars]

During coil negative control testing with the test light, was the test light connected to battery positive? Thanks Paul

[@ScannerDannerPremium]

Battery negative. Sorry I didn't mention that in the video. Why is the test light so bright on coil negative you may ask? Answer: (short answer) low ohm coil, high ohm light

[@AUTOREPAIRGUIDE]

ScannerDanner Premium How about testing coil positive control testing .Where do you connect the test light? battery positive or negative? Thanks

[@ScannerDannerPremium]

Negative

[@poolmotorrepairguyFL]

The Florida pool pump motor bearing repair guy When Service Calls Longwood approved ! that was good info

[@JoelAutomotiveInaction]

Paul, thanks for this nice video.I have a question when having crank no start , what will be a average spark kv minimum you are looking for? or varies vehicle to vehicle. I was wondering because I had 00 4.3 Silverado can jump during cranking 30kv good bright known good . also a had no start 00 civic was jumping barley 25 kv at distributor cap ,had new distributor when I started doing my testing however old wires and plugs. I thought it was too weak I also hook up the lab scope but I got lost there because I am not good on the secondary side of it. I replace the wires and plugs and started fine I at beginning I thougth 25 kv was weak spark any advises to help me in future diagnosis thank you are the man

[@nickayivor8432]

Good Evening ScannerDanner 🙏 ✨ take care,have a great day ScannerDanner 👍 Nick Ayivor from London England UK 🇬🇧

[@GlynRobinson]

Could a ignition control module on a 2003 4.3 cause a P0300 random misfire? I’m getting that code when the RPM is above 2K driving. I thought about taking the module off and clean then reinstall with new thermal paste behind it.

[@ScannerDanner]

Most likely plugs and wires with that symptom, though I'm guessing your already replaced them?

[@GlynRobinson]

Yes. Already replaced plugs and wires. The engine runs fine. Real strong. It’s not a misfire that I can feel. I’ve replaced the crank sensor (with a relearn) and distributor too. I’m going to check for vacuum leak today.

[@rafaelortiz982]

Ok so they saing the ligth should keep a contenius ligth or brigth?

[@erikturner5073]

I've ran into situations where the coil passed the ohm test perfectly and there were controlled switching at the negative side of the coil and still no spark. Still no spark. Cool was still faulty. The ohm test isn't the sure fire way to determine coil condition. It's rare that a bad cool passes the resistance test but it happens.

[@stevensantos369]

Im in the middle of troubleshooting a '93 5.7 chevy Silverado. It starts fine. Won't stay idling. Have to pump the throttle to keep it from dying when driving as it wants to stall until I can get to higher RPMs ( approx 2000 on up) in which it does very well and will red line of I let it. It just doesn't want to idle while in gear but will for about 20 sec in park or neutral. When driving in hesitates badly and you can hear the intake "ploomp" like a minor 'backfire' until the desired higher rpms are met to get the truck shifted and gaining some mph but will stall once cruising speed is met. TPS voltage reading starts abt .5v and smoothly increases as throttle is slowly opened. Throttle body has black soot in it now. Has new plugs,wires,cap and rotor. Iam suspecting a weak coil spark and will strengthen as rpm increases as does alternator. Am I on the right track here? What else should I test? I figured it has fuel if the engine will run at high rpms. Btw, I did a resistance test like you did on the good coil with the ground wire on ignition post. I didn't get any reading on my ohmmeter. I did see a testlight spark but it didn't look as robust as yours. Somewhat thin and yellow and blue spark. What about the ignition module in the distributor? Test it? How? No change when unplugging Oxy sensor. And timing is off but doesn't improve when adjusted. I can't set it If engine won't idle. If you don't have time to make a lengthy reply I would appreciate some initial thoughts. Iam pretty good at looking if Iam pointed in good direction. All the vids that show my same symptoms with same engine have a different fix. This vehicle is old but new to me. Don't have any history on it.

[@denisemoseley9662]

Have you found the issue to your truck? I also have issues with the same year and model like yours and can't seem to find the sours. What was yours?

[@stevensantos369]

@@denisemoseley9662 not yet. It's my friend's truck. I've already replaced most of the electronic sensors and devices like coil, whole distributor as well. It will throttle nicely. It's getting fuel but It won't idle. You need to throttle it to keep it from dying. Once warmed up you can kind of throttle high and it will run but you can definitely hear a surging that is not caused by the throttle. It's independent. Only two things I haven't checked, and the latter will be the first checked...ECM or, the crankshaft position sensor. That was my first instinct...but, I had to listen to the local "experts" that argued that it wouldn't start at all if it was CPS. I say bullshit, my first failure of any CPS was on a car and it was getting harder to start and sometimes stalls at stop signs. But it was running. I replaced the CPS and it totally fixed problem. I'm a smart guy and vindicate myself often but there are many people among me that seem to have the need to show they're superior to me. I'm not easily impressed so they're just wasting energy and just annoy me. I usually go with their suggestions after mine are dismissed just to prove them wrong without having to run their noses in it.

[@johnbladykas125]

Excellent video. Where can you get pin for back probing

[@ScannerDanner]

www.amazon.com/shop/scannerdanner Thank you!

[@JahanZeb1976]

Excellent testing procedure. Great video tutorial mate. Interesting that you confirmed in the end about the secondary short.

[@ScannerDanner]

LearningZone I know, first glance I said shorted primary winding for sure. Then when I thought about it, a shorted primary winding can lead to a no flicker result when using the test light. It is the one variable that makes the test light test inaccurate. This is what made me want to redo the test and look more closely.

[@jamessmejkal8803]

The test pin is really hard to see and was not pointed out, but it works. What tester is being used, just noticed Snap On ouch. Enjoyed the video, Thanks.

[@mebcconstructioncompany5674]

Hi SD i have a problem getting 12 volts to my coil [i have replaced cam, crank sensors & new coil confirmed relays are in good condition; had the computer completely refurbished, all fuses are good. I have studied your You Tube post on ignition system design operation; troubleshoot a no spark condition and others. I need a direction to try; car is a 1998 volvo 2.4 non turbo , one coil. i don't have funds to buy wave form scanner, i cannot get 5 v France voltage; please help. H. Morris

[@appealinglife]

I have no spark on my 1986 oldsmobile ciera cutlass 4 cylinders.The secondary is reading 4500 instead of 11000 like this video shows. The test light is solid on positive and it doesn't work at all on negative while cranking the engine. What should I do next ?

[@ScannerDanner]

Switch your test light to battery positive and tell me if it lights on coil negative. Important though, you MUST have power going to coil positive for this test to be valid.

[@appealinglife]

@@ScannerDanner I switched the test light to battery positive and there is no power there.

[@markcather5239]

Hope not to late for help?? Neg wire White and red Pos?? That comes from Ing Mod?? So if light goes on and off coil ok? Also can I check pick up coil with out removing dist ?? Thank you in advance

[@charlesdowns1691]

will a vacume gadge help diagnose a bad coil correctly? mine drops 1" or maybe 2" at times. can i trust this also?

[@ScannerDanner]

I've never used a vacuum gauge to troubleshoot ignition problems

[@charlesdowns1691]

@@ScannerDanner +thank you for reply. i like this video+technique with ignition also.. on my vacume gz+ it normally ready steady 18" normal engine but has been dropping 1" 2" chart says possible ignition issue. ( appreciate it+have a good day )

[@colinmckinnon1812]

I have the same 90 pickup mines not getting spark to the ignition coil. I thought it could be the pickup coil in the distributor or the ignition switch. It was running great stalled. I’m going to have someone turn the key while I look to see if the distributor is spinning I have a 305 tbi so not sure what it could be I know there’s no crank position sensor and I don’t think it would be cranking if the ignition switch was bad. Please help

[@jonhsmith2706]

Did you figure it out?

[@jvgilyard1126]

So if the test light doesn’t flicker that means the coil is good? I have 90 c1500 5.7 at , coil and distributor less than 2 years old, was running fine, then crank no start. No spark at coil.

[@ScannerDanner]

If the test light doesn't flicker, you need to move away from the coil as the problem and toward the ignition module and distributor pickup coil. I have another video that will help you kzbin.info/www/bejne/nKPEY2mvrt6WY6s

[@MechanicForGMCCars]

Wuld those gm modules work if you aplly positive power from baterry and pulse it with only negative wia pick up coil ore vice versa wuld it still work?

[@ScannerDanner]

I've been able to trigger these module with a test light to battery positive on and off of the pickup input positive terminal

[@MechanicForGMCCars]

@@ScannerDanner I did see that testing experiment on google I was wondering wuld I need to put resistor to the positive pulse side and conect baterry power to it ore bridge 2 terminals as shown in that google picture that I found I was wondering wuld the negative pulse terminal do the same thing? Because I want to use twin gm ignition modules and make cinde of waste spark ignition system I do not have twin trigger coils so I must some how improvise . I dont know if me singel trigger coil culd handel 2 x 4 pin gm ignition modules. I want some thing similar like jaguar 2 ignition coils and their gm amplifier only problem how to bypass pulsing problem??? I do have more parts for that car I was wondering if I can use 2 pick up winding and use them in series ore pararel configuration to get corect pulse polarity so I dont fry me ignition modules.

[@marcs5790]

So you went from battery negative to red coil wire. Then battery positive to the white coil wire?

[@ScannerDanner]

No sir, battery negative for both tests

[@donaldsmith4542]

I've got a fusblie link ground under coil should it read ohms from red n white to coil I have no connutiy from coil to ground on motor

[@aliciacastillo5468]

Any reason why my k1500 keeps burning up new ignition coils, like for 15 minutes it runs fine but then it shuts off and after crank agailn it fries up the coil, any idea where should i start looking?

[@ScannerDanner]

Ignition module issues. Cheap parts. Open plug or coil wires

[@lenweiss9515]

Danner!! My car's broke down in the bar parking lot. No spark. Had a new coil and put it in. Still no spark,and no test light. Module?

[@donaldmiles3232]

Correct me if I'm wrong but isn't .06 ohms a short. I don't think 3.7k ohms is considered a short.

[@bobdelaplage690]

Hi paul, 2 questions that may sound silly cause im absolute beginner in electric basics...1. how does your testlicht “ survive “ the high voltage? Second question, i hear u say “ want the spark to go somewhere” does it mean it harms the coil when high voltage has no way out? Sorry for my laymens level...Bob from Belgium Europe

[@ScannerDanner]

1. The incandescent test light can handle secondary kv because it is very low amperage and the bulb filament simply provides a path. Do NOT try this test with an LED test light! 2. Yes, if the spark has "nowhere to go", that energy builds up in the coil to the maximize level and it will start to look for another path. This can and will damage the coil itself and also the driver for the coil.

[@bobdelaplage690]

@@ScannerDanner thanks mate! Keep safe! Enjoyed yr in depth knowledge and enthusiasm, try to see all of it, what a nice job you do, also contributing to us, over the world, to help us fix our cars! Bless u!

[@Mopardude]

Great video, it help me diagnose a problem I was having.

[@ryanclay959]

I have a 1993 Chevy 4×4 pickup truck Cheyenne 1500 model with the JB5 brakes and the first gen 4.3Lt V-6 and I have no spark. On the wiring diagrams it shows the larger pink wire going to the ignition switch and white going to speed control, the other two thinner pink and white go to the distributor and on mine for the larger pink and white I do get power to the pink with ignition on but no ground connection to the large white and on the smaller pink and white that go to the distributor I get no votage at all. I believe that the wires going to the distributor are just signal wires to get spark but looks as if my problem could be no ground from large white wire? Please let me know when you are able to

[@Agethalove]

H3rj4j4

[@lavonn1108]

Having issue on 1999 vortex 5.7. I keep blowing out ignition coils what could be doing that??

[@JD-ml7cg]

Does a 1992 f150 need a crank signal to start?

[@ScannerDanner]

A 92 would be a distributor engine and the pick-up inside of the distributor would essentially be your crank signal, so yes, it does.

[@jasonmcadam5126]

thanks for the video . Im having trouble with my 88 chevy truck , I changed Distributor shaft ignition module , also coil still no spark ...

[@ScannerDanner]

Some voltage measurements would help us here

[@Z06Doug]

Note , I see the MSD coil. I have the same set up and use Msd, 6A, wires, and coil. E 3 spark plugs, change cap and rotor pretty often. Went thru a spell of changing the cheap after market Chinese distributor modules. But on a recent trip, the MSD coil failed on the road.No warranty as after 1 year since time of purchase. I had a new stock coil in the truck ( with spare dist.modules ) and have replaced the coil again with a new MSD COIL, BUT IS THIS A MSD problem? Never had a stock coil quit. BTW, went to the Holley or Accell dist modules, no problems.

[@FLYChicken34]

What if you put your test light to neg and pos and get no light? My distributor is getting power but it’s not reaching the distributor if that makes sense

[@ScannerDanner]

Year, make, model, engine size, and the wire colors you are testing and where you are testing them at, please. Thanks!

[@joekamer7779]

So my only problem is I can’t see which wires your touching trying to trouble shoot a 1994 chev k1500 5.7 No start have no one to crank so trying figure out how to test coil , distributor pick coil and ignition module

[@ScannerDanner]

Coil primary (positive and negative) the negative side should flicker

[@appealinglife]

@@ScannerDanner if the negative doesn't flicker what should I start looking into?

[@ScannerDanner]

@@appealinglife steady light that looks like coil positive? If yes, then that means there is no control of the coil. So you have an input problem (pick-up coil) or a module problem (if we are talking about an old GM system) Do you have injector pulse?

[@markcather5239]

Sorry not too clear w question. R/w wires from ing mod in,under distrib? Again is wht hot and red neg. And if pick up coil is bad do I need to pull dist out? Also is that what you are calling cam timer. If not where to locate,test??? thank you for help. Truck has been sitting for awhile. C/K 3500 Crew cab 1995 454 true gas hog .........

[@ampload]

I went to buy a test light for this purpose and this is what the seller told me ?.. "This is a standard test light. When clip is connected to grounrd ... and point is connected To 12v + pos. It will light the light. No grd indicator. It is a hd light. We use ours in trailer shop every day." Djk950 "If the module being tested is sending a + plus this tester will read it but you cannot get pulse width or elaps time. The tester will only turn on and off with the pulse. I would not use this to test ground signals on any type of control module such as your ICU or ECU. If you want to check pulse + or - properly and safely I would check out a Power Prob that has an isolated ground terminal. This will be the safest way to keep any power surges from going through your control modular and causing damage." Please help with your opinion... Thanks again

[@kennedywong9854]

Can starter draw more voltage to cause no spark to ignition coil?

[@omarcanales6975]

@Scannerdanner yeah the rotor spins wen the motor turns! and yes the distributor came with a new cap and rotor and ignition control module 😞....... this is driving me crazy lol is there anything else that can cause no spark!!!!

[@ScannerDanner]

+Omar Canales did you do the bypass test? The one I sent you a video on?

[@ignaciorios7026]

I have a 95 chevy Silverado with a code 12 and 73.do I have to buy distributor do to no pulse to module

[@ScannerDanner]

Code 12 is a normal flash code. Chase the other code

[@eusebiegherman8225]

Having the same no spark issue on my 1988 350 gmc carburated engine. Simple test/solution?

[@gamertime7605]

I have a 96 gmc pick up.has crank but no fire..changed plugs and wire and rotor and rotor cap.coil has spark .what can I do to get the Engine to fire over?

[@ScannerDanner]

check your fuel pressure next

[@rockyroad90]

I have a 1989 k1500 4WD 5.7 giving me fits! When I go to start the engine some times, especially when cold it kicks backwards like the spars is too far advanced and sometimes not. But when it is crunk it surges at idle or when holding the accelerated: up down up down. Ive tested throttle position sensor, map sensor replaced fuel filter and pump. Tbi injection looks good. I’ve unplugged the wire going to ecm to set timing, coolant sensor, o2 sensor, knock sensor and even esc module and still surging. Check slack in timing chain by manually turning motor and watching distributor rotation ( less than 1 in slack watching harmonic balancer marks) . I’ve pull valve covers to check rockers and push rods..nothing out of place there! I’m almost to the point of doing away with ecm and putting and carb and vac advance distributor on it but I hate to let it beat me. Any help will be appreciated. Thanks 🙏🏻. Oh and I would put it in a shop but nobody around here works on anything over 30 years old.

[@ScannerDanner]

How does it drive under load?

[@rockyroad90]

@@ScannerDanner Poorly. Very under powered.

[@ScannerDanner]

@@rockyroad90 I'd do a fuel pressure test next. Without hearing it run, it could be fuel or ignition but we need to a least rule out fuel psi kzbin.info/www/bejne/g4PdaHRqhbWnbLM

[@ampload]

Awesome Video as always ! Paul Do you have a "Link " for you test light that is safe testing on a ICM Module - Coil I want to purchase one like yours... Thank you my friend.

[@franciscovera828]

There's plenty of them videos where he proves convenient ional light is safe. Plenty of controversy on subject but I use it all time too.amp draw on regular testlight is low and safe.

[@danielsproelectricalservic5805]

If light is dim on distributor what is that a sign of?

[@davidl5121]

Pointing the testlight to the control wire where is the clip grabbing to?

[@ScannerDanner]

Battery negative unless specified, sorry

[@davidl5121]

@@ScannerDanner okay cool thank you

[@fredautos]

Great teacher Paul danner

[@erniesmith6295]

I have a 85 gmc pick up 1500 5.0L that just shut off going down the road and hasn't started since it has fuel and what I think is weak fire it's in time if anyone could give me some suggestions would be very appreciated

[@30YearOldBunta]

Okay so I'm diving deep into the hole on this. My 2002 Infiniti Q45 does have an isolated ECU ground, the engine ground is shared by a bunch of stuff and I'm getting a build up of resistance in the car after about 10 minutes of driving. When the build up is bad, I get flickering in the LED cabin lights, and engine timing is pulled, at it's worst it'll be 0° timing. I thought I had this fixed last comment lol by simply sanding the coils down and spraying the exposed wire with contact cleaner as the car could pull over and over but it came back, and upon further inspection the entire car has corrosion in the wires (some of which are already thin). Also the fuses (the ones related to that circuit) have soot and discoloration. I stopped being a parts changer and started being a tool buyer lol

[@savagelife9199]

I know this is a old video but I have a 97 Nissan Sentra gxe 5speed crank but won't start no spark at spark plug wires but whole distributor assembly is new need your help thanks

[@ScannerDanner]

External coil or does it live inside of the distributor? Do you have injector pulse?

[@savagelife9199]

ScannerDanner when I first noticed it had no spark an no fuel so I hot wire the fuel pump an the pump started running idk I'm lost what could stop both of them at the same time an I replace fuel pump , fuel filter , spark plug wires , whole distributor assembly , crank sensor an still doing same thing

[@davidraper2718]

I love your videos and how you break everything down and how your doing everything and what it's for. I have a question what is the cooler for that the ICM is bolted to on a 94 Ford ranger 3.0

[@Truthsearcherforever777]

U made a book? Where can I get it? Will it have all your knowledge or that’s only in your class? Meaning u made a small book but all your knowledge is given in class?

[@ScannerDanner]

Both my classes and my book are available from my website at www.scannerdanner.com Thanks!

[@Truthsearcherforever777]

@@ScannerDanner I just purchased it bro. Can’t wait to read the book.

[@ScannerDanner]

@@Truthsearcherforever777 thank you so much!

[@chrisstandley5703]

What if I have power to my coil once I turn my key I lose power is that the ignition switch not the cylinder the switch

[@ScannerDanner]

Year, make, model and engine? Some systems will not power up the coil during cranking without an rpm signal. You'll get an initial "prime" when you turn the key on and then it will turn that circuit back off until there is an rpm signal. Why? Because the fuel pump is on the same circuit.

[@MikeSmith-nu9wt]

No coil negetive control the white wire ? White with black stripe is good ground , but no signal , darn bucket truck , that white wire goes into the boom for starting and stoping the engine from the boom , three relays and a ford selinoid , not sure which relay i need for coil im assuming it runs back to the computer under the hood , to the est output sig pin 9 , i think ..musquitos kicked me off my mystery for tonite

[@ScannerDanner]

Did you fix it?

[@nik-j3t]

I don't have 12v on those two wires until the engine starts. Is that an issue?

[@ScannerDanner]

No, that's fine, you working on a Dodge? They share ignition coil power with the fuel pump circuit. Other manufacturers do the same

[@nik-j3t]

@@ScannerDanner it's a GM. Not sure of year or what it came from. It's transplanted in a Toyota FJ40. It's ran fine and last week it just died going down the highway. Didn't have tools to diagnose on the road. Towed it home and while towing I slipped it into gear, let out the clutch and it started running. It cut out again on a drive after that that but only periodically. Since it's intermittent, I'm trying to figure out what it might be. Fuel pump has 12lbs at throttle body so I'm focusing on spark. If it dies again I was thinking to unplug the timing connection. Will that bypass the ECM and timing advance? If it runs then it has to be control module or pick up coil? Right?

[@ScannerDanner]

@@nik-j3t are the electronics and wiring Toyota or GM? I'm not going to be able to help you beyond what I've shared in this video. Especially if it's half and half electronics. And the fact that you don't have power to that coil until you crank it says this is a Toyota electrical system

[@nikpottala8378]

@@ScannerDanner all the engine electronics are GM via a Painless TBI wiring harness for all the engine. It’s a 90s model TBI 5.7. Nothing is Toyota until I get to drivetrain. All straight GM engine components and wiring connections and ECM. So I’m a GM if that doesn’t have power, what could be the cause? ICM?

[@ScannerDanner]

@@nikpottala8378 Every single GM in this time period has power to the ignition coil with just the key on. The fact that you don't until you crank it says something was altered

[@michaelbarnes5857]

I have a 2000 Silverado V6 4.3 I replace the coil I replaced the crank sensor but the coil still not getting not fire I had to control module check they said it was good I I had it checkout than once . please help

[@ScannerDanner]

It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there. Paul Danner (ScannerDanner) www.scannerdanner.com/forum/post-your-repair-questions-here.html

[@robertcaston3170]

Michael Barnes check your relays and fuses first if thete all good then check the ignition module if thats all good or your model does not have it then check cam and crank sensors ok .

[@rrmech11]

Can you do video on non communication from a shorted module ipc abs bcm where one of theses keeps the pcm from communicating

[@ScannerDannerPremium]

On my radar for sure!

[@rrmech11]

Worked on a 99 s 10 blazer with no communication had to go to module splice pack

[@bobdelaplage690]

Another thanks to you, i could make my old volvo spark again, there is a (in) famous Bdpwire that runs close behind block, with almost no space to manouvre to the flywheel...so preventive maintenance is left out at this item...the heatcycles destroy the wire mostly, or the bdpsensor was never made to outlive the extreme mileage the red block volvos were to be proven 30 years after leaving factory...also saab has these extreme high mileages, that blow your mind...swedish very high quality steel that was specially designed for the cylinders( sometime it is mentioned”nicasil”)....seldom motors have to be rebuilt here , neither the superb dieselmercedes, they also reach 600 ooo miles...

[@jimdavidson5208]

That MSD coil might be rated at 3600 ohms on the secondary side. My Accel 300+ CD coil is with 0.3 on the primary side. One thing I just learned was you can test with test gear all day long. Still not got it running. A real test is with engine running under LOAD. Either the coil/module works or not.

[@shotdog4237]

ScannerDanner, what would keep a module from advancing, its a 93 350 tbi, new, coolant send, new module, tps, cap, wires, plugs, map works, knock sen. seems to work, when you rev, the timing goes jumps up maybe 5 degrees and comes right back to 0, idle's ok, runs but no power, i thought it was a fuel problem till i checked the timing,

[@ScannerDanner]

There is a tan/blk wire (that goes to the module) that has a single plug disconnect, on the main harness on the firewall? Make sure it is plugged in. This is your timing connector.

[@shotdog4237]

ScannerDanner, yes, it's hooked up, does the egr module control ant timing events? if not i'am gonna have to assume the computer bad!

[@shotdog4237]

i have the mt2500 snapon and when i plug it in i don't have power to it, i have to use the 12 volt plug on the side of the gm obd1 modular, all the fuses are good and the cig lighter don't work either! i'am wondering if that 12v comes from the computer or the fuse box, maybe only half the computer is working, the tan\black wire has 4.49 v

[@ScannerDanner]

12 pin ALDL does not have a power feed, you need the external one for the MT2500 on that model. Post this to my forum for additional help and make sure you include our exchange here too. www.scannerdanner.com Thanks! Paul

[@shotdog4237]

thank you ScannerDanner, i didn't realize the 12 pin had no power, thanks for the help, and i went down and had an emissions done and it passed? i couldn't believe with what little power it had, it passed! i checked the MAP and it worked with a vacuum pump but i think it may be working differently on engine vacuum, cause when you try to accelerate it doesn't want rpm up, and when you slowly let off the throttle and it gets just about at your cruise speed you can feel it wanting to go, kinda like a plugged jet! or letting off the throttle gives the MAP more vacuum, i find it sooner or later! but thanks for the help.

[@robertpaulis439]

If you're already an electrician or a "sparky on the job" this video is great but for the rest of us out here plugging a probe in some +/- orifice without showing just leaves a novice lookin' to just move on.

[@ScannerDanner]

But I can help you! I have videos to guide you to this level

[@greygoosemafia]

which is the best spark tester to get?

[@ScannerDanner]

It doesn't really matter. The ones I use are listed on the tools page if my website if you're interested. Thanks!

[@greygoosemafia]

I was looking at theat lisle one wiht the long ground wire. excellent. It's much cheaper on your page. thx man.

[@rarewaxartifacts5247]

Hey everyone, I have a 92 k2500 5.7 350 TBI. The issue is that after the truck warms up when I put it in drive if I don't have my foot on the gas it will die. It idles great when in park and if I two foot the pedals at stops it runs just fine but as soon as I let off of the gas it will hang around at about 700rpm then within a minute it dies. I've replaced fuel filter, egr, and ICM. The strange thing is it only started after I replaced the faulty ICM. I looked through several of scanners videos but am probably missing something simple or overlooked the correct video. Any help is appreciated, thanks in advance everyone.

[@stevensantos369]

I have a similar problem with alot of hesitation and stalling on same engine. What did you find out as I noticed no reply? I did a tune up on this new-to-me pickup. No improvement. TPS seems fine. Iam suspecting a weak coil as I've heard that can happen even though one may have spark. Please reply.

[@wilsonvalentin1738]

I have everything new on my 98 chevy 3500 and I still have no spark at all i change everything

[@davidturner2535]

Sounds like your timeing is off .check your distributor also.

[@The_gordo_channel]

Im only getting the probe to light up during crank.

[@ScannerDanner]

That's normal on some systems as the coil is powered on the same circuit as the fuel pump

[@The_gordo_channel]

@@ScannerDanner hmmm ok thanks. I replaced my coil still no spark, thinking maybe time to change out the ICM. I cant think of anything other reason to not be getting spark at the coil, I have checked all fuses. It's a 91 4.3l s10. any Ideas? To clarify, the red wire coming to the coil is hot and and the white wire is NOT negative correct? its signal from the ICM?

[@ScannerDanner]

@@The_gordo_channel on a 91, that white wire would be the coil negative that yes, does go to the module. Sometimes it is split and the second wire will extend to the tachometer. Questions: 1. Do you have injector pulse (TBI system or the Vortec CPI)? 2. Do the white and red coil wires look different from each other during cranking? Then should, the white wire should flicker and my guess is it doesn't) So this means we move toward the pick-up coil or the ICM. The injector pulse question will answer which of those two we are going after.

[@The_gordo_channel]

@@ScannerDanner i really appreciate you taking the time to get back to me. When you were doing this test with the light probe, was the probe grounded when testing the negative as well? Or did you move the probe aligator clip the positive terminal when testing the negative? I havent checked injector pulse yet i will do so this weekend. I really wanna get this thing back on the road for my uncle. Thanks again.

[@paulfiebke3909]

Loved this one keep up the good work

[@exmotorsports]

Fantastic stuff Paul.. Thanks Bud 😎👍

[@mikeanderson1994]

if i have little spark not good from the coil but still wont start and i have fuel what could be the problem ?

[@ScannerDanner]

It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there. Paul Danner (ScannerDanner) www.scannerdanner.com/forum/post-your-repair-questions-here.html

[@mikeanderson1994]

Thank you sir

[@shawnhartling9956]

Good video but when you turn key on put power to the coil the coil as power good ing to the cap if it rolls over or not there is always power there where in was testing

[@88honcho]

So the control is the white?

[@ScannerDanner]

Yes sir

[@88honcho]

@@ScannerDanner so if the coil was good, the test light would go out? And coil positive is on the white wire?, and coil negative is which?

[@ScannerDanner]

@@88honcho coil negative is the control wire as it is a ground side switched circuit. No spark and coil negative flickers = bad coil. No spark and coil negative does not flicker = no control = do not put a coil in it, other tests must now be done to confirm ignition inputs and control module function

[@songwriteroc]

Hey have no power to coil on c10 v6 i can hot wire truck starts up fine help !! Please.new coil

[@DirtyMikeHoncho]

As long as you fed voltage from a place where the key controls you will be just fine. Sound like a broken wire or something. Dont matter where it gets power as long as it gets power