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

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TTT

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Good, with that out of the way, purchase those diagrams, cost you 0.007% of the Q7 value and lets move on to a test plan with a multimeter?
 
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KraftwerkTurbo

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Good, with that out of the way, purchase those diagrams, cost you 0.007% of the Q7 value and lets move on to a test plan with a multimeter?
The wiring diagram does not show any values to test, neither for 'trailer plugged in' nor 'no trailer connected'.
 
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TTT

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No problem, we make our own value to test, but you only have to trust me?
 
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jettarv

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Check fuses 9 to 12 .. locate on right in luggage compartment.

Fuse assignment on fuse carrier ST3, red

1 - Vacant
2 - Vacant
3 - Vacant
4 - Vacant
5 - Fuse 5 on fuse holder F -SF5- 15 A - Rear Seat Entertainment (9WP, 9WK)2) Multimedia system control unit -J650- 30
6 - Fuse 6 on fuse holder F -SF6- 20 A - Comfort system central control unit -J393- 30
7 - Fuse 7 on fuse holder F -SF7- 30 A - Rear lid control unit -J605- Motor in rear lid control unit -V375- 30
8 - Fuse 8 on fuse holder F -SF8- 30 A - Rear lid control unit 2 -J756- Motor in rear lid control unit 2 -V376- 30

9 - Fuse 9 on fuse holder F -SF9- 15 A - Trailer detector control unit -J345- 30
10 - Fuse 10 on fuse holder F -SF10- 15 A 20 A1) - Trailer detector control unit -J345- 30
11 - Fuse 11 on fuse holder F -SF11- 15 A 20 A1) - Trailer detector control unit -J345- 30
12 - Fuse 12 on fuse holder F -SF12- 30 A 25 A1) - Trailer detector control unit -J345- Hinged tow attachment ball head motor -V317- 30
 
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SaVAGeSoot

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The wiring diagram does not show any values to test, neither for 'trailer plugged in' nor 'no trailer connected'.
Why are you playing mechanic when you don't even know the rules of said game? :banghead:

What did your code tell you?
1 Fault Found:
02539 - Terminal 30 from Control Module
014 - Defective
What did someone who unlike you, read the SSP on how to read\understand VAG WDs tell you this means?
Un-switched battery power.

-Uwe-
So get the WD, and check for battery power (aka hot wires) at the control module. What values do you need to know that you have battery power? :confused:
(hint, put the meter on the battery terminals before you do your check... that value is what you're going to be looking for at the other end of the wires, over by the module)
Now look at your module, pull the 12pin plug out, and check for battery power (hint: that's a value not listed on the WD) at pins 9, 11, &12 as per WD.
If you're missing any, check the fuses.
 
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KraftwerkTurbo

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Thanks for the tip. Ordered (fancy Tekosha and cheap generic to test). I had bought a trailer harness with connector box to make it easier to test the output. But have NOT found good information yet what resistance the Audi/Tekosha controller needs to 'see' to recognize 'trailer hooked up'). I would then modify the harness accordingly to simulate 'trailer use' to measure output. With the real tailer hooked up, code reset, I saw inconsisten/varying voltage going to the trailer brakes, and code returning. Initially (not sure how long or how many brake applications), I have full brake voltage, but after a while only low voltage, and Tekosha showing error.
 
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KraftwerkTurbo

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If the wiring and/or fuse between the battery and the module is faulty.
I checked all fuses in the right side trunk. All "active" positions have good fuses. Which fuse 'feeds' "Terminal 30"?
 
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KraftwerkTurbo

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Why are you playing mechanic when you don't even know the rules of said game? :banghead:

What did your code tell you?

What did someone who unlike you, read the SSP on how to read\understand VAG WDs tell you this means?

So get the WD, and check for battery power (aka hot wires) at the control module. What values do you need to know that you have battery power? :confused:
(hint, put the meter on the battery terminals before you do your check... that value is what you're going to be looking for at the other end of the wires, over by the module)
Now look at your module, pull the 12pin plug out, and check for battery power (hint: that's a value not listed on the WD) at pins 9, 11, &12 as per WD.
If you're missing any, check the fuses.
The 12 pin (RED) connector has battery voltage (14.4) at the 3 pins (large pins). I did not see numbers on the connector. If those are 9-12, then:
pin 1: 0.01V pin 2: 14.4V pin 3 0.4V, pin 4 13.3V (NOT full battery voltage), pin 7 1.0V pin 8 4.0V, pin 9 14.3V, pin 11 14.3V, pin 12 14.3V
 
   #31  

SaVAGeSoot

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So what did you just confirm by checking for power at the module?
 
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SaVAGeSoot

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Color me curious.... can you show a picture of what your brake controller is telling you?
 
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KraftwerkTurbo

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So what did you just confirm by checking for power at the module?
Nothing to confirm it to. Don't have 'supposed to be values'. Still don't know which of those pins is the mysterious 'defective Terminal 30', why it is 'defective', and what the underlying cause is for it being 'defective'.
Color me curious.... can you show a picture of what your brake controller is telling you?
Yes, will take pic in the afternoon. Last (when error code is present): NC (for no connection or so, but will also post what it means). When I can clear the code, it does work, typically only one time (then code is triggered again). But last time, was NOT able to clear code with VAGcom, so "nc" shows.
 
   #35  

SaVAGeSoot

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Nothing to confirm it to.
OMFG.... so you have no idea why you're checking what you are checking! :banghead:
Don't have 'supposed to be values'.
I went through this already.... HINT: you've just confirmed that the module is receiving power on the INPUT side.
Without WDs, you don't know what the outputs are, or where they should be going, etc.

Do you even know if you have proper connections at the brake controller 4 pin connector?
You said you have no brakes.... what sends signal to the trailer brakes? That's right... the blue wire off the brake controller.... have you checked that it outputs anything?

I also don't know what brake controller you have, but most will "register" input (when you press the brake pedal) even if there's nothing connected to the trailer socket.
What do you see on yours when you press the brake pedal?
 
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   #36  

SaVAGeSoot

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I did not see numbers on the connector.
Let me try a different approach......
This is from an Touareg, so more than likely, similar to what your Q7 of that vintage has.....
Can you show me your connector or module that doesn't have numbers on it?
 
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   #37  

KraftwerkTurbo

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I also don't know what brake controller you have, but most will "register" input (when you press the brake pedal) even if there's nothing connected to the trailer socket.
Prodigy P2
 
   #39  

KraftwerkTurbo

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Let me try a different approach......
This is from an Touareg, so more than likely, similar to what your Q7 of that vintage has.....
Can you show me your connector or module that doesn't have numbers on it?
This is the module in the 2012 Q7 (it has only 2 connectors, not 3 as your photo shows): https://drive.google.com/file/d/1lplzrNFy33-Uyng_vxORdnsHydyT6Ohx/view?usp=sharing
The connector does not have pin number. The module has.
Here are the pins of the 12 pin connector:https://drive.google.com/file/d/1eLSaFGGtGiFzInr8hbaE2deuU3LxQWGn/view?usp=sharing
Voltage on 12 pin (no numbers on the pins of the connector): https://drive.google.com/file/d/1VyZu2818g4_TUjRAeYgrWJxSasJ9uSdg/view?usp=sharing

12 pin connector wiring (3 pages each):

Still looking for that 'Terminal 30' that is 'defective'. Not menioned.

Copied the 12 pin connector diagrams out of above docs into one jpg:
 
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   #40  

KraftwerkTurbo

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Do you even know if you have proper connections at the brake controller 4 pin connector?
You said you have no brakes.... what sends signal to the trailer brakes? That's right... the blue wire off the brake controller.... have you checked that it outputs anything?
Will check blue wire output on controller (may not get to it today). Would that be the 'defective Terminal 30' ?
?
 
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