2014 Audi Q7 No crank No start transmission stuck in park

[aysix]

Hey Yall,

Back into these audis. I have a Q7 with the 3.0T. It will not start, or turn over. It's got electrical but when you turn the key, nothing. Also...no codes.

I found a few videos on youtube about the power line going to the TCM, I checked mine. There was corrosion, but I fixed that. Still no dice...no change.

With the car not allowing me to get out of park, and wont start in neutral i'm inclined to believe this is a trans/tcm issue.

Any ideas?

[MattyMarkey]

Hey Yall,

Back into these audis. I have a Q7 with the 3.0T. It will not start, or turn over. It's got electrical but when you turn the key, nothing. Also...no codes.

I found a few videos on youtube about the power line going to the TCM, I checked mine. There was corrosion, but I fixed that. Still no dice...no change.

With the car not allowing me to get out of park, and wont start in neutral i'm inclined to believe this is a trans/tcm issue.

Any ideas?

Check the battery? Check fuses?

[jbain2]

Is VCDS reading the TCM? I’m assuming same issue with your push to start?


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[aysix]

So I been cracking at it all day today. TCM is good, ECM is also good. I got desperate and started shaking some wires around. The harness to the relay next to the battery under the drivers seat made a noise when I was messing around and then the dash cycled. Huh.

More shaking around, the MF thing started! BUT then when i cut the key off...wouldnt turn off. So, right now it's narrowed down to that relay or the wiring to that relay. I'll report back. This had me frustrated because it had all the symptoms of the TCM wire being corroded on the Q7 in the wiring loom (put keywords there so people can find on google) which wasn't actually my problem i guess.

I'll dig deeper with a new relay and all that.

Oh by the way. While I was messing with the harness I had a new issue. on the dash it said "please remove key", then I removed the relay and that went away. Bizzarre. But I'll figure it out.

[aysix]

Update - I manually click the relay under the drivers seat and it starts up like nothing was ever wrong. I put a new relay in today and it didn't fix the problem. So my next guess is I gotta figure out what powers this relay.

I can't beleive I got back into these audis man.

[jbain2]

I think I remember reading about something like this. It may be related to the key lock cylinder and relay. Let me see what I can dig up.

Also for the 4L platform audiworld is a better resource. Lots of knowledge from some long time owners there.


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[aysix]

I think I remember reading about something like this. It may be related to the key lock cylinder and relay. Let me see what I can dig up.

Also for the 4L platform audiworld is a better resource. Lots of knowledge from some long time owners there.


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Cool to see you're still active on here. I appreciate that, and I will do that. Thanks for the advice.

[jbain2]

Cool to see you're still active on here. I appreciate that, and I will do that. Thanks for the advice.

Likewise. I absolutely love my TDI Q7. Thing is a highway monster and 28-30+ mpgs is hard to beat for a vehicle this size.


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[aysix]

I ended up getting OBD Eleven to do more diag. I don't have VCDS anymore since I thought I was done with all these audis...

-Can't scan any modules with key on acc without the terminal 15 relay jumped
-When the relay is bypassed, I can start and drive, but cant turn it off since the relay is bypassed. Soon as I cut the relay off, the car shuts down

I don't think there's a TCM issue. However there's some issue between the ignition and terminal 15. Does anyone know where I can find wiring diagrams for the ignition switch? I'm wondering if there's a problem with the ignition switch sending power to terminal 15...but I really have no idea how that works.

[jbain2]

I ended up getting OBD Eleven to do more diag. I don't have VCDS anymore since I thought I was done with all these audis...

-Can't scan any modules with key on acc without the terminal 15 relay jumped
-When the relay is bypassed, I can start and drive, but cant turn it off since the relay is bypassed. Soon as I cut the relay off, the car shuts down

I don't think there's a TCM issue. However there's some issue between the ignition and terminal 15. Does anyone know where I can find wiring diagrams for the ignition switch? I'm wondering if there's a problem with the ignition switch sending power to terminal 15...but I really have no idea how that works.

PM me. I have the manual in google drive. Can send you the link.


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[aysix]

After reviewing the JBain manual (thanks again!), I’ve narrowed down the possible causes of this issue.

What I’ve ruled out:
The ECM and TCM are functioning properly. I confirmed this by bypassing the 373 relay (terminal 15) under the driver’s seat—when jumped, the car starts and drives.

Replacing the relay didn’t change anything.

Potential culprits:
Ignition switch – Since this doesn’t require programming, I can grab a used one from eBay for around $100 or check local part-outs. I can also buy one from audi for 400 bucks but no thank you.

J518 module (steering lock under the dashboard) – This controls power to the terminal 15 relay and is known to fail in the C6 A6 and Q7 models. However, it typically logs fault code 00288 (Reference http://wiki.ross-tech.com/wiki/index.php/00288 ), which I haven’t seen in my case. Replacing it is a hassle since it needs to be reprogrammed. There’s an aftermarket emulator available, but it requires extracting data from the original unit.

Comfort Control Module (in the trunk) – Similar situation as the J518, requiring data transfer if replaced.

This issue is frustrating, but I’m determined to fix it. If someone else finds themselves in the same boat, I hope this helps in their search. Forums are still king.

I found the ignition switch, which volkswagen calls the "start authorization switch E415" and it's duties attached

[MattyMarkey]

Let us know the outcome if that officially fixes it. I have seen the reports of no start in park, but those resolutions do not seem linked (so far)

[aysix]

Let us know the outcome if that officially fixes it. I have seen the reports of no start in park, but those resolutions do not seem linked (so far)

It seems like theres more than a few things that can cause it, bad TCM, wiring to TCM, or anything above. Maybe even key. I ordered an ignition switch, if that's not it then I guess I have to take the J518 apart and fix the relay.

When I put the key in the ignition, the steering wheel lock doesn't make any noises. None of this makes sense to me. Sigh.