Circuit ID and Integrity Testing Part 4 (SD Premium)

This is part 4 of a 5 part class I taught last year. You can find the other parts to this series here www.scannerdanner.com/scanner...
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For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
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On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@ScannerDanner]

This is part 4 of a 5 part class I taught last year. You can find the other parts to this series here www.scannerdanner.com/scannerdanner-premium-chapters/chapter-10-signal-circuit-integrity-testing.html The clip I posted the other day (test light and life lesson) was pulled from this video and I know you guys liked that, so I figured I would post the entire video here on KZbin for you guys too.

[@dimisrambodimisrambo7285]

MY DEAR FRIEND, WE WISH CHRIST IS RISEN AND EVERY FAMILY HAPPINESS. I AM AN ENGINEER FROM GREECE AND I WATCH YOUR VIDEOS.YOU HAVE REALLY HELPED ME VERY MUCH IN THE DIAGNOSIS OF TROUBLES. CONTINUE TO GIVE US YOUR KNOWLEDGEI WILL WATCH YOUR VIDEOS WITH CARE. SORRY BUT I DO NOT SPEAK ENGLISH SO I TRANSLATE MY TEXTS .CONTINUE THE GOOD WORK YOU ARE DOING. THANK YOU VERY MUCH. DIMITRIS GREECE.

[@tomastarvydas63]

I admire the fact that Paul diagnoses vehicles which has the newest technology with something as old as incandescent light bulb

[@robertsmith2956]

I hadn't thought of that. To get rid of our good repairable cars they got rid of light bulbs to stop repairs.

[@rodolforamirez9436]

Amazing the level of knowledge putting it in plain English. I’m a follower from Los Angeles and that is very much what I do for a living for the last 25 years. By far the best professional way I seen around. Thanks for all the great information!

[@ScannerDanner]

Thank you my friend

[@jscons7424]

Thanks Scanner, I hope to meet you oneday even though we re thousands of miles away, I desire to sit in your class and experience your presence in the classroom... you re my mentor, YeShua bless you

[@Hurlburton]

Thanks Paul for the classes

[@ScannerDanner]

Thank you for joining!

[@Pablo_Automotive]

Thanks a lot for another great explanation about voltage BIAS, the incandescent light is always a good "friend" for us. 👍😊

[@robertsmith2956]

probe on battery will trigger the relay certifying the wire can handle the signal. If bat + won't close relay wire bad.....

[@johnemberton408]

The teacher I learned the most from in A&P school had a similar teaching style to you. Everything he said - no matter the subject matter - would click. He frequently used the phrase "for our practical purpose" in the place of "always", "never", etc (your asterisk problem in this video). That was always helpful because it eliminated the need for him to detour, even for a second, into explaining that there are variables and other cases where this isn't true. When it came time to expand on the complexities of an issue later on, he would simply review the subject as we had previously learned it, and explained that we we're about to investigate the "for instances" in detail. This was great because we already had the base foundation of the knowledge needed to expand on the issue. One example of this is learning basic aerodynamics. You can't honestly say that Bernoulli's principle "always" applies. "For our practical purpose" when learning about how a carburetor functions, when air velocity increases - pressure decreases. They're inversely proportionate. BUT, this isn't ALWAYS true. Once we took the dive into what happens once you break the sound barrier - things get wonky. Avoiding that caveat gave me confidence in the current subject matter.

[@marvinpostadan3484]

One of the top in the automotive industry.

[@itridz5860]

Soon I'm gonna start my own workshop I'll be the best in town because of you Paul thank's man

[@ScannerDanner]

That's awesome man. Thank you!

[@tracydiller9378]

Sometimes oldschool commen sense is better.Great video Paul as always.I have learned ALOT from your teaching.

[@jamesd6247]

Thanks for the video. I'm just a backyard guy who drives a 88 Ford that never seems to break down, but it's really fun to keep learning even though I'm way beyond what I set out to learn. We appreciate you.

[@alreadygotone9180]

Amazing amount of information!! This level of detail and description is so helpful!

[@LifeSavingDefense]

FYI your explanation of low resistance = high voltage and high resistance = low voltage also works for diabetics and insulin resistance but there’s kind of a bias as a diabetic with high insulin resistance usually has a high blood sugar reading which is misleading because that sugar isn’t being used for energy because the insulin that would transfer it to energy is blocked… 30 yr paramedic who also works on cars and right now I have 2003 dodge truck with a no communication problem with the computer. This video is perfect because I did pull the asd relay and got 12v on a digital meter and wondered why. I only have old school incandescent test lights but didn’t think to use it but now I will. Everything in life is a puzzle.

[@JimmyMakingitwork]

I feel schmarter with every ScannerDanner video I watch!

[@neverstoplearning382]

I just love this man. Thanks for all you do for this industry. Best regards mr Danner.

[@paulfiebke3909]

Thankyou for all your hard work and all that you do keep up the good work and God bless you and your family

[@gixxercorona]

Incandescent test light is so underrated, cheers Paul for the lesson 🍻👍🏻👌🏻

[@danishzaman9320]

May God bless you for spreading this experience and knowledge to others 🙏 you're a big help...keep up the good work!

[@frankiev-tech4630]

My man Paul! Awesome lesson and enjoy how you apply real world events to these students...you're so on point on the customer's perspective when it comes to diagnostics...totally happens to me once in awhile when it comes to multiple issues on same problems. And you're right...gained massive customers over the years for always to never rush a job...that's always something every student should engrave in their heads to keep their jobs. To me that's the key is to put consequences for doing a half ass job. I hope for the future for these students becoming bright for what's coming with all this technology. Something to add to always question everything that the customer experienced prior to the repair...for them to ask the how, when, why, duplicate the problem...especially on the feel the customer experienced or if they had the problem checked by someone else.

[@stephenmarshall5302]

SD Premium all the way. If your not on the premium then I suggest you sign up 🤘. Loads of content of this quality on there

[@ScannerDanner]

Thank you my friend

[@spelunkerd]

Wise remarks after 16:12. The world is often more complicated than first impressions would suggest.

[@IAMNOSLEEP]

Thanks for sharing Paul... Cheers.

[@isalmankhan1]

Superb, what a great lecture on Bias voltage👍 Thanks for educating us SD👍 Stay Safe SD❤

[@mg2361]

Great video Paul! I work for a John Deere construction and forestry dealer and Deere tells us (its in the service manual) that the only way for us to check the driver's in our Vehicle controllers is with (ready for it) an incandescent test light. They just don't tell us to do that with the Engine controllers (why?? I don't know).

[@michaelr6205]

Have been a student of your KZbin & Premium content for years, really like this type of teaching format. Real good stuff! Thank you for sharing your knowledge. Would love to see more of this same style.

[@ScannerDanner]

All of our newer lectures carry this style. The SDP 2.0 playlist in particular. Have you seen it?

[@michaelr6205]

@@ScannerDanner No I guess I need explore around a bit more.

[@ScannerDanner]

@@michaelr6205 no problem! Thank you so much

[@scientist100]

I always use a test light to load the circuit and if the wire is a heavy gage such as the fan wires or fuel pump wire or the AC fan, then I use a 5 amp bulb (headlamp bulb) at least.

[@davidostring1289]

Thank you for sharing your knowledge. Keep up the good work.

[@SuperSecretSquirell]

Yay, no coked-out chipmunk voice lol. In my field (Caterpillar tech) we have 5 or 8 volt bias voltages. Initially, I was like "why are they adding all this stuff making it more complicated?" What I eventually learned is that it actually makes our job even easier (if you understand the fundamentals behind it). When my code says "xxx sensor voltage low", it tells us that we have a short in the circuit. If you unplug the affected sensor and you get an "xxx sensor voltage high", it tells you that your wiring integrity is not suspect. That leaves you with a sensor or ECM/driver issue. It will even do the same for outputs (solenoids, relays, etc) by telling us whether the amperage is high or low.

[@cwj9202]

Your statement at @ 26:00 is correct in that context. When the computer grounds an actuator, I always warn my greenhorn mechanics to understand the system before sticking a test light into one of those circuits.

[@pulsiui4003]

Thanks for your wisdom, always 💙

[@jeremiahschaefer6670]

I like to use a variety of test lights like a digital one with 06mA draw, a red bulb with 68mA, a tag light bulb and socket with 284mA, 9006 bulb with around 4A, and an old sealed beam headlight that pushes 10A.

[@shaunsautorepairs5410]

always good to be in a class with scanner danner....

[@ScannerDanner]

thank you my friend

[@frankjackson9821]

I thank you so much for this information! Saving up for your book.

[@ScannerDanner]

Thank you Frank

[@SuperSecretSquirell]

Came to watch again and thought I'd share an interesting function of our (CAT) ECMs. If you have a driver that has a short to ground, the ECM shuts down that driver until it gets power-cycled and reset. We rarely have bad ECMs unless they're installed in a bad location and they end up with water ingress or the housing corrodes through. They've gotten smarter and have moved all of the ECMs (except the engine one that's mounted to the engine itself) into the cab of the machine.

[@ScannerDanner]

We see that too, where a driver is disabled with a current code. Clearing that fault and cycling the key is the only way to get it to turn on again. Thanks!

[@renicj1714]

Thank u 💖 sir ... Explanation.. time .. and effort .. respect

[@JoaoSilva-cu3ky]

Dear Paul, Thank you for all your shared knowledge about automotive eletronics diagnosis. I have a question regarding to power consumption of test light.What is the recommended power to enssure that driver is in good condition without burn it? Best regards from Portugal. João

[@triggera3851]

Awesome video

[@tomtke7351]

good advice: high-side/low-side switching!

[@georgebonney90]

Thank u mr danner👍

[@krishill6505]

All of your videos are as close as I can get without being in class. definitely want to get your premium to be in class, which I could be at the college in person

[@ScannerDanner]

Thank you! Look forward to having you

[@PhillyDee215]

Class with Scanner Danner👍

[@thebaldmechanichardatheari1124]

Years ago when I went to community college for mechanics we were told that a relay does a electrical job and solenoid does a mechanicly job like on a starter.

[@JimmyMakingitwork]

Relay and solenoid both use an electrical coil to operate. But I never really stopped to ponder that one does an electrical job and one mechanical, interesting.

[@ScannerDanner]

technically the relay does a mechanical job too

[@htownblue11]

Voltage rarely automatically equals current or load capability! Another knowledge bomb dropped by SD!

[@lahirudilshan8439]

Thanks lot sir❤️

[@AW-ty5qi]

The diagrams at my dealer have the transistors and bias voltage resistor with monitoring line shown in the control units it’s a blessing

[@ScannerDanner]

that's cool, factory diagram are starting to show this

[@papapetad]

Never, always etc... In Permaculture, we learn there is only 1 answer that is always right for every single question: "It depends".

[@marktirabassi7160]

Your great

[@likezdislike]

Hi Dan. I just want to ask if my pcm circuit has a pull up driver does it mean my bias voltage should be positive(+) only and pull down 0volts/ negative? 12:40

[@frankjohn4302]

Remember seeing this for some time and was confused by it.no flow chart as far I could remember never mentioned bias voltage.then I came across your channel .if I could pay you back I would.

[@ScannerDanner]

You have by this comment my friend. 😊

[@mediilbrahim2835]

Hi Mr Paul thanks for the lesson I have a question first do we get the bias on the output control circuit only (how to recognize the circuit is it input or output)?? and most be a bias in all cars!? ..

[@ScannerDanner]

You can and will find a bias on input and output circuits! Come join my classes and watch the rest of this series.www.scannerdanner.com/join-scannerdanner-premium.html Hope to see you there

[@Ken-1]

The master

[@siphiwowowo4940]

Your videos are so good I am Staying in South Africa if you have a book that you wrote I would really love to buy it.

[@ScannerDanner]

You can purchase it from my website at www.scannerdanner.com I have an eBook too, which would be most likely the direction to go as shipping the paper book to South Africa will be a problem. Thank you!

[@lautaroalberola]

hi paul!! question.... the are different types of bulbs for the testlight, if the circuit is using around 100 or 150mA in the relay control side, and i use a testlight that's using 500mA up to 800mA for substitute that load (relay coil), can i cook the driver? don't know, but the PCM may have a current limited device for protecting itself? i think it's important to know this, i mean if we are going to substitute a load with the testlight we need to make sure how much current is using. thank you so much for sharing this!!! Thanks to you and other friends of you i'm starting to do diagnostics, i love it!!! Love from Argentina!!!!

[@ScannerDanner]

Yes! A resounding one, on cooking a relay driver with and 800ma test light. I wouldn't rely on the current limiting circuit if there even is one on a relay driver

[@moneymikesupplymusic]

Hello paul, I am having a TPS check engine light code, I monitored my Throttle angle % at full throttle and that was at 40% I hooked up a volt meter to my Throttle Pedal Postion Sensor and I am getting a 5 Volt refrence.

[@ScannerDanner]

What is TPS signal voltage?

[@moneymikesupplymusic]

@@ScannerDanner See I ben trying to find a wirring diagram for the vehicle. I purchased it twice thru shopkey and I dont know how to log into pro demand to link it

[@stspringer2003]

What happens if you put an incandescent test light clamp on the battery positive post, and touch the test light probe to the relay base ground pin?

[@PicassoPete]

Hi Paul, would it be a good idea to explain about DMM’s versus Analogue type meters with respect to their ohms per volt internal resistors. (you may have done it in earlier video’s.oops, my bad then lol.) An example, especially with bias voltages/resistors, would be to show the minimal effect on a circuit with a high ohms per volt DMM as against the use of an analogue meter/incandescent test lamp. Just a thought. Love the video’s as always...Regards Peter A.

[@ScannerDanner]

Yes of course! All of this is discussed in my classes. Thank you!

[@TheCurtis0207]

Hey I saw one of your videos of testing a crankshaft position sensor and I tested mine the same way on a 1998 jeep tj 4.0 and on my ground I got 400 millivolts while cranking. If you could let me know if you know what that could mean that would be awesome. Thanks

[@ScannerDanner]

Bump the key and look for 5v at times and then 0v at other times. 400mv during cranking could be a normal average voltage of the on-off square wave

[@casper8092]

At 24.12, here is the answer to the question raised "Why 10.90V when engine cranking but relay removed." 12V are both supply to the transistor as well to the external SUPER high resistor. That means, these two inputs are at the same potential i.e. 12V. 1. Now, with RELAY unplugged, when engine is cranked, both are still at same voltage 10.90 (due to starter). Since both are at same potential, there is no lower potential for current to flow although the resistor is connected. It basically implies that the high resistor just sits between the same potential. 2. Now, with RELAY plugged in, when engine is cranked, DIMM reads still about same voltage 10.80V. The confusion here is "Where does this 10.80V come from? Does this voltage comes from the transistor or the external constant supply voltage?" Here is the answer. Compare the 2 circuits i.e. n side of transistor till to the 86 pin side of relay, and the positive side of the RESISTOR to the same 86 pin side of relay. There is negligible amount of resistance in the first circuit. However, there is super high resistance (over 100 KOhms) in the second circuit. So when engine is cranked, CURRENT ALWAYS CHOOSE THE PATH OF LOW RESISTANCE. It simply implies that the high resistor does not even exists at all. So, current flows through the transistor. Hence, this 10.80V is essentially the voltage coming through the transistor.

[@sergejpanov5543]

I have Toyota Corolla 2004, automatic transmission, 135K miles, It starts and drives good but when it's cold it doesn't respond well to acceleration when stopped at a light. It needs to be revved up to 3000 RPM before it starts picking up speed. Once the car runs for about 15 min, and the engine is warm, it drives with no issues. I cleaned the MAF sensor, changed transmission fluid (no filter change), changed the air-filter, oil and oil filter, and antifreeze as part of the maintenance. No diagnostic lights have popped up. What should I do or change?

[@rwrobs777]

Hi Paul !!...another great electrical VLOG...I'm your "Corvette Guy" on your Premium Channel and had a quick question on AC so maybe I can get you here and if not I'll get you on the Premium side....a friends 97 Corvette AC stops working after a long ride...works fine normally when first started....question about "AC Request"...if I press the AC mode button while watching the AC Request and I see YES does that tell me that the HVAC Module is sending the class 2 message to the PCM and the PCM is receiving it ???...older Corvettes used a 12 volt wire to the PCM....I've checked all the inputs...RPM, AC pressure sensor, ECT, ambient temp sensor and all looks good !!...using my U activate I can get the compressor working on the load side and the AC mode light stays on...I don't see the PCM grounding pin 85 on the AC Clutch relay control pin..I also checked at the PCM to see if the PCM was providing the ground there but NO... thanks !!

[@ScannerDanner]

The AC request signal is being read from the ECM data PID list right? If so, then yes, your HVAC module is sending the signal. Are there any other inputs, low psi or high psi cut offs or an evap temp sensor? Tough call on the ECM driver for that relay failing only when hot. I feel like we are missing an input

[@rwrobs777]

@@ScannerDanner Hey Paul, thanks so much for getting back to me !!...YES, reading the AC Request data PID from my Verus Pro...no evap temp sensor on this car...AC "presssure sensor" voltage good, ambient temp sensor on HVAC not reading minus X degrees and all others look good...when this is happening only when hot I'm thinking increased resistance and maybe the PCM driver failing when hot but maybe no. Friend drove the car all day yesterday and couldn't get the AC to fail...so thanks again and if you and the Fam are down in Southwest Florida next winter look me up and we can have a big BBQ down here and take the boat out for a cruise !!...oh, another thing if this AC Request is a Class 2 data message I wonder if I can scope the data wire and jump the HVAC and PCM splice pack wires together along with the data wire and when I push the AC mode button with key on if I can see some data packets being sent out over the data wire ??

[@ScannerDanner]

@@rwrobs777 these older GM computers did fail for sure, just make sure that the control wire is tested right at the ECM (you said it was missing when measured at the relay) before making that call. Make sense? And heck yeah, I'm always up for a barbeque!

[@rwrobs777]

@@ScannerDanner Paul, I did check to see if the PCM was indeed grounding the circuit at the PCM (high resistance ?) but still no good !!...thanks for the info and I did see something in SI that said if you don’t see the AC Request the HVAC Module is bad and if you do see it change the PCM..NEVER mentions anything about checking inputs !!...I hate these troubleshooting trees...bad info !!

[@tnamen1307]

Another thing... Say there is no 12 v supply on the n side of the transistor. Now, what would be the behavior of the transistor if an input voltage say 3 v is send to the base of the transistor? What will be the voltage readings at the 2 n sides separately? Will they show the same voltage 3 v which is supplied to the base of the transistor?

[@ScannerDanner]

Good question, but with no 12v supply on the collector, this would be a computer problem, unless you we missing a main power feed to the board. In which case you wouldn't even be focused on one particular output, because you'd have a no com and a no start. If the computer itself is not supplying 12v on the collector, then yes, for sure, you'd have low to no voltage on the output and it would not function and normal troubleshooting procedures would identify that. Hope that makes sense

[@nickwilson1476]

@20:19 so if I connected the "control" relay terminal that comes from the computer to a ground, I would fry the computer? Is that because too much amperage would fry the little diode in the computer?

[@ScannerDanner]

Yes sir, on this design (power side switched), with a short to ground on the control wire, the transistor driver in the computer would get cooked.

[@pigeonsil240sx]

my question is how do we know if the signal/control wire is supposed to be sending out a signal to pcm or supposed to receiving a signal from pcm? is this just something we need to learn from each sensor or is thisn info in factory service manuals?this confuses me and very important for me to know.

[@ScannerDanner]

Signal wires are input circuits and are being "watched" Control wires are output circuits and are being controlled. Come join my classes and I can teach you this stuff for sure! I offer a 14 day free trial, so come see what I have. Based on your question, I'd recommend starting in my chapters 2 and 3 playlists. www.scannerdanner.com/join-scannerdanner-premium.html Hope to see you there!

[@iiNgONYaMa]

What's the most affordable set up /kit to enter into being a precise diagnosis and repair tech and avoiding parts changing? Really strapped for cash but really interested in this.

[@ScannerDanner]

unfortunately that is a complex questions and even more complex answer. You want to get started with troubleshooting electrical and electronic systems on cars right? You will need a service information subscription, a decent DVOM, a good test light ot two or three lol, and a decent scan tool that provide you with bi-directional controls. Oh and you will want a lap scope too.

[@iiNgONYaMa]

@@ScannerDanner thank you for the response. Really. At least I know what to start with and where to look towards. I'll look at your Amazon page for specific suggestions.

[@ScannerDanner]

@@iiNgONYaMa Also, post to my forum. It is free to join. We have over 20k global members and you will get some suggestions from others who live and work in your market. There is not a one size fits all with this type of stuff. www.scannerdanner.com

[@tonyt1554]

How often do you see a computer have 1 bad power or ground supply but the computer stays almost fully functional causing only one circuit issue. To give an example lets say it has no control of an evap. solenoid but everything else is functional and the computer/circuit is good.....does this happen often? Thanks ScannerDanner!

[@ScannerDanner]

It almost never does. If I thought real hard I could maybe come up with less than 5 examples of that in thousands of cases.

[@armory3379]

HI Mr Paul Danner . SD Premium! What’s the difference here on A youtube Channel and on the ScannerDanner Premium for you?,...Thank you!

[@ScannerDanner]

The primary difference is classroom lectures (like this one). I have hundreds of them there. Also hundreds of exclusive case studies. To date there are 470 videos with about half of them classroom lectures and the other, case studies that you guys are familiar with. Thanks for your interest! www.scannerdanner.com/join-scannerdanner-premium.html

[@Texsrt4]

Power probes have a reasonably low impedance, much lower than your standard meter. They load the circuit way more than your ohm meter, though it would be less than an incandescent test light. I question your point about trusting the LEDs on it. I’d love to see you test it!

[@ScannerDanner]

The power probe (because of its low impedance) will pull down certain bias voltage signals, causing a variable when performing circuit integrity testing. This is outside of the LED vs Incandescent test light variables. Thanks!

[@Texsrt4]

@@ScannerDanner I don’t think I laid out my point properly. The power probe is effectively a voltage meter. Meters have high impedance to resist electron flow while testing voltage which it what makes them safe to use on line voltage equipment. The power probes lower impedance allows greater current flow while testing, which would load a circuit. But the terms high and low are relative. I guess I could look at the tech specs.

[@Texsrt4]

@@ScannerDanner thank you for responding. I do appreciate your expertise

[@ScannerDanner]

@@Texsrt4 I understand that, thanks! I'm saying that is a disadvantage at times, that's all. I have the PP4 and it's a great tool!

[@tnamen1307]

Tell more details how the extra resistor behaves when the driver is activated? When driver is off with relay plugged in, 0 v on the control side. When driver is on with relay plugged in, 12 v on the control side. How does this 0 v changes to 12 v??? It's very confusing. Please explain more.

[@scientist100]

Computer supplies power from the transistor and the relay coil consumes it through resistance. The computer has it's own transistor that changes just like a relay would but the bias voltage is what's extra in the computer board, as Danner said, it is used to monitor opens or shorts in wiring integrity.

[@ScannerDanner]

sign up for my classes my friend, I can teach you for sure and you seem to have the thirst for knowledge, which is necessary to succeed www.scannerdanner.com/join-scannerdanner-premium.html

[@scientist100]

Power probe has a short fail circuit design but not sure if it would trip a weak transistor if supplied the opposite polarity. I would say that it would cook the computer driver but whi knows. I know I wont try it 😅

[@ScannerDanner]

oh it will definitely cook a driver if you are not careful

[@samueltaylor6961]

I think you can see bias voltage with a power probe because you get a voltage reading but neither positive or negative leds light up

[@ScannerDanner]

A power probe has less internal impedance than a digital voltmeter and will pull the bias voltage down

[@Nypartcannon]

How can I get the book ? Thankyou brothers

[@ScannerDanner]

from my website at www.scannerdanner.com Thank you!

[@Nypartcannon]

@@ScannerDanner Thankyou brother

[@andrewlindsay5075]

If your not a prime member and have the book your seriously missing out get the book and follow along and learn

[@ScannerDanner]

Thank you Andrew!

[@albertsautodiagnosticsllc2130]

You say unplug it if you have bias your done move on..but how do you determine if a circuit is supposed to have bias voltage or not??

[@ScannerDanner]

you won't know for sure, experience helps, but it is easy, no bias, then you use another method to verify circuit integrity. I cover that in this series too. Hope that helps. It is too wordy to explain the other method here, but it involves jumping the ref to the signal circuit

[@albertsautodiagnosticsllc2130]

@@ScannerDanner hey thanks for the reply. I'm going to take my ASE A6 on the 29th and I'm trying to cram in as much studying as possible I'm subscribed to your premium out of all the lessons and videos what ones do you recommend I go back and familiarize myself with that will help me prepare for my test

[@ScannerDanner]

@@albertsautodiagnosticsllc2130 thank you Albert! To be honest, the A6 Electrical/Electronic Systems, basically the lessons and chapter playlists is where you want to be. I cover this type of thing in just about every chapter

[@albertsautodiagnosticsllc2130]

@@ScannerDanner 🙏 thank you I've been learning from you for the past 2 years I'm positive I'm going to pass but just wanna be prepared

[@ScannerDanner]

@@albertsautodiagnosticsllc2130 If you've been with me that long, I have complete confidence you are prepared my friend

[@nancylewis7142]

☆☆☆☆☆

[@MrRcgillet]

trouble shooting a computer with an incandescent lamp isn't BS because computers are low current devices and a test lamp isn't you have to know what the current output is to connect to it with a lamp. normally you are right in an auto circuit. if they could make a low noise electrical system for a car. you could be in real trouble

[@ScannerDanner]

I always preach that before you start using a test light, you must know what your test light draws and also some knowledge of the current draw of the circuit in test. All stuff both written in my book and practiced regularly via case studies right here on YT and on my website in SD Premium. This is but a piece of a class. Thanks!

[@robertleifeld225]

Great... The old Scanner Danner is returned. Much better than so much bs from brothers shop where we learn little or nothing.

[@ScannerDanner]

You like the lectures then huh? I have hundreds more on my premium channel www.scannerdanner.com/join-scannerdanner-premium.html

[@ScannerDanner]

What you are seeing, if you've been with me a long time, is my son is now the editor and he includes things that I would have always cut out. So if you are seeing a difference, it is from that, and I understand that some of you may not like it, but I won't be changing it back. This is his style, and he is my right hand man, and I love what he is doing. You apparently don't like the humor and banter between the Danner boys, but to call it b.s. and you aren't learning anything??

[@saidsaleh1988]

hello ScannerDiner! could you put Russian subtitles, it would be very polite of you, thank you

[@ScannerDanner]

I have no control of that and KZbin got rid of community contributions. Im sorry

[@HAm-ru8qk]

what do you want translated, I just asking my self

[@PicassoPete]

I’ve said all along the only thing wrong with this business is cars and their effing owners lol.

[@MrRcgillet]

a ressitor is a current device ( limiter) and volt and current are inversely proportion. Sorry you need teach current flow.

[@ScannerDanner]

I do! This is one part of a 5 part class

[@ScannerDanner]

Something else, at the end of this lecture I had some added pictures using ohms law and talking about a voltage divider circuit like we are dealing with. It has the current flow measurements you're asking for. And to be honest, it isn't needed. Understanding the voltage drop between two resistors is all that is needed here. So sorry, I disagree, discussing current and or measuring current is not needed here as long as one understands that current flow doesn't change throughout this circuit.