How To Read/Dissect an Engine Computer Wiring Diagram

Reading wiring diagrams starts with an understanding of your fundamentals in what can be shared, and what cannot be shared between sensor circuits. The 5v reference and sensors ground circuits can be our guides to dissecting a wiring diagram!
The vehicle being used is a 2012 VW Jetta 2.0L TDI system
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[@elitesoccerblogs4947]

Please do more videos like this of dissecting wiring diagrams they help out so much!

[@ScannerDanner]

I have so many of these on my website and in all of my classes. It's still only $11 a month for over 450 hours of training. Hope to see you there www.scannerdanner.com/join-scannerdanner-premium.html

[@thebaldmechanichardatheari1124]

Doing a great job of explaining. You have a gift in how you make your students and public understand your methods. Very good work.

[@lovetolearn5253]

I miss videos like this and hard diagnose cases. I know you post them on your premium channel but unfortunately my health declined and i can't afford that channel any more. I lost my alldata to. I would diagnose 1 to 2 cars a week because thats all my body would let me. Ive watched all your videos at least twice and learned a tilon thank you. I just watch know because i enjoy.

[@ScannerDanner]

Email me at [e-mail] copy this message in your email and tell my wife I said we would open it for you for 6 months. Thank you! Hope this uplifts your spirit a bit

[@lovetolearn5253]

Thank you 👍. I truly appreciate it.

[@d.jeremiahmulbah5210]

great man thanks a million bro. we dont have a school in my country that teach us this kind of lesson. thank to GOD and the internet i can learn from you. let God blessed you with long life.

[@ScannerDanner]

And may God bless your hands and your mind to continue in this field my friend

[@williamgagnonroadboxservice]

Thank you again Danner you make it look easy takes a lot of practice

[@stryker4374]

This is great! I hope to one day be at your level of knowledge!

[@ScannerDanner]

You can do it!

[@scottmarshall6766]

A damaged harness (rub through?) causing an internal harness short between the 5V reference and a 12v conductor could also do it but would require the ground be opened by the damaged harness as well. An extreme longshot, but I've seen a few cases that defy the odds through the years. Thanks for your great content!

[@Pablo_Automotive]

Thanks Paul for another class

[@northernpatriot9078]

I gotta brush up on diagrams schematic reading thank you 😊

[@Greg18m7]

Amazing amazing video thank you so much this will help me immensely with my diags

[@jakemartin4305]

This is why I sub lol ❤

[@richhelm21]

Paul being concise, clear & logical as ever. Great explanation, and why understanding fundamentals is key.

[@ScannerDanner]

Reading wiring diagrams starts with an understanding of your fundamentals in what can be shared, and what cannot be shared between sensor circuits. The 5v reference and sensors ground circuits can be our guides to dissecting a wiring diagram! The vehicle being used is a 2012 VW Jetta 2.0L TDI system

[@isalmankhan1]

Thanks for sharing SD👍🏻👍🏻👍🏻 Very very important stuff😍 Stay Blessed SD🙏🏻🙏🏻🙏🏻

[@cullenmiller8170]

Sounds like a case of the green crusties or a rodent molesting the wiring. Also congrats on the 400k subscribers. I just noticed that. 👍👍

[@V_Vladimir_V]

Неожиданно и интересно!

[@medch4193]

الله يرحم والديك

[@antsupertramp]

Woooo!

[@wyattoneable]

Classic SD!

[@joeandgod1]

On Scanner Danner premium, when you click on one of the chapters, is it showing me the latest video first? (at the top). Or not necessarily.

[@ScannerDanner]

There is a new videos list in the drop down menu of the SD Premium tab after you login. Thank you!

[@joeandgod1]

@@ScannerDanner Ok. I'll look for it, thanks.

[@ScannerDanner]

​@@joeandgod1feel free to ask those questions on the premium videos too! I see and respond to all questions on all of the videos for you guys

[@dominikg4334]

What about if you place one lead of multimeter on battery + and other one on ground on sensor will that not show a voltage drop bettwen two different points on that circuit?

[@ScannerDanner]

There are other ways of circuit ID, but what if that circuit already has a problem? Which in this case does! The multimeter will not be your friend here with circuit ID. Not in this case. But in others, yes.

[@dominikg4334]

@@ScannerDanner thanks for the replay yes that's right. I was thinking about no wire diagram and checking just from your head as meater may show readings where wires will not be connected but when you connect to sensor it may show nothing I not sure if that's the right way of thinking .

[@luckyj13k8]

CAN THERMISTORS SHARE A 5V REF. CIRCUIT? THANKS IN ADVANCE.

[@ScannerDanner]

Not externally from the computer, no. They do tap into the 5v regulator but there is a current limiting resistor in that circuit before it gets there if that makes sense.

[@luckyj13k8]

understood perfectly thanks Paul.

[@awedakehinde9709]

I need all data link sir

[@ScannerDanner]

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[@JasenFromBoston]

treyway!

[@calholli]

I don't understand.. You keep saying that they can't share a 5v ref.. but then you go through and show how they are all sharing it?? I don't get it. (4:45) ... You show Fuel pressure sensor, Engine speed sensor, EGR pot and EGR position sensor, etc.. are all sharing the 5v ref. What am I missing? It clearly shows that all the grounds are tied together (as you showed first) -- but also many of the 5v ref's are tied together too (which you also showed). So when you say that they can't share it-- what do you mean? ........... edit: Unless you're just referring to only a 2 wire sensor; Where it has no signal wire; so it has to use the 5v ref as the signal wire??

[@80fly1992]

He was saying a 5v ref cannot be shared between a Hall effect sensor like a crank sensor or cam sensor with a thermistor like a temp sensor and it can’t be shared with a potentiometer sensor like a TPS sensor but it can share a ground

[@richardcranium5839]

yeah i caught that too. lips moving faster thanthe brain???? i think he meant signal return

[@richardcranium5839]

since a three wire sensor and a two wire sensor can share a ground (not always) and 5v refs can share, the signal return is what the computer is reading cant.

[@ScannerDanner]

Signal return is another name for a sensor ground.

[@ScannerDanner]

The 5v ref that is shared between pots, psi sensors, hall effects cannot be shared (externally from the PCM) with thermistors. This was the identifier between the 5v ref and the sensor ground circuits (signal return is another name for a sensor ground). Sensor grounds can be shared between all inputs!

[@Brian18741]

Great video but it's still over my head. 😭 Is your premium subscription suitable for absolute beginners?

[@ScannerDanner]

100%! Start in my Basic Electrical Concepts playlist, then start at the beginning in Chapter 1. www.scannerdanner.com/join-scannerdanner-premium.html I'll do my best to answer all your questions too. Hope to see you there!