2012 Q7 - Trailer brakes not working - 02539 - Terminal 30 from Control Module014 - Defective

[SaVAGeSoot]

I can't do this any more..... you don't have a diagnostic bone in your body.
You have WDs, but don't know how to read them.
Please read the SSP on how to read WDs so that you know what you're looking at.
After that, assuming that you know how to use a DVOM, please read your code.... especially the part I'm highlighting below.

1 Fault Found:
02539 - Terminal 30 from Control Module
014 - Defective

If you get that far, let me know what it sounds like you should be checking next.

 

[KraftwerkTurbo]

Can someone tell me what and where that "Terminal 30" is?

 

[PetrolDave]

Can someone tell me what and where that "Terminal 30" is?

There is no single "Terminal 30" it is a generic term used for any connection that has permanent (i.e. non-ignition) power.

 

[SaVAGeSoot]

As per prior attempts, if you would educate yourself on what you're trying to do, and would read the information you've been directed towards, you'd see this type of stuff....

DIN Standard 72 552
This standard applies to the terminal designations for circuits. The purpose of the terminal designation system is to enable accurate
connection identification from conductors (wires) to various components when diagnosis and repair is necessary.
Examples of DIN standards for terminal designations are shown below:
1 Ignition coil primary
4 Ignition coil secondary
15 Ignition switched, on and start
30 Battery +
31 Ground
31b Switched Ground
50 Starter control
75/X Load Reduction/Ignition switched on only

Since you're not going to bother doing any of that, let me tell you what you've just checked thus far while continuing to ignore all the advise and information at hand.
You've just checked all the inputs into the module, and they have passed.
Now, there's inputs and outputs.... let's see if you can figure out what's left..... hint: there's an indication in that GREEN code description that I've highlighted....

 

[SaVAGeSoot]

Go to pg.95 here to get a better list of designations used in this standard.

 

[KraftwerkTurbo]

There is no single "Terminal 30" it is a generic term used for any connection that has permanent (i.e. non-ignition) power.

Thank you. So a "Defective Terminal 30" means that permanent power (to the module itself?) is missing? Which would indicate the problem is 'upstream' (from ??? TO the module)?

 

[SaVAGeSoot]

 

[KraftwerkTurbo]

Thank you.

 

[KraftwerkTurbo]

Thank you. So a "Defective Terminal 30" means that permanent power (to the module itself?) is missing? Which would indicate the problem is 'upstream' (from ??? TO the module)?

Is the "Terminal 30" the T4y2 ? https://drive.google.com/file/d/1ODL89fShqHnmNsW5NeDaIXzo8JEkq8Tn/view?usp=sharing
If so, fuse S87 "Trailer towing attachment thermal fuse" in one of the 3 fuses in the trunk (those are all good) or a different one (says 30A in the WD, but 15/20 in Fuse Box Diagram I have as pdf)>
C9 15 Trailer detector control unit -J345-
C10 15/20 Trailer detector control unit -J345-
C11 15/20 Trailer detector control unit -J345-

 

[PetrolDave]

Is the "Terminal 30" the T4y2?

If you have the wiring diagram and have learnt how to read it then you should be able to see what fuses and what wires are involved.

Start measuring at the pins shown as connected to terminal 30 on the trailer module with a multimeter, then trace back using the wiring diagram until you find the problem (connector, fuse, splice, etc.)