andyhart21

Well I have now fitted a brand new Varta Silver Dynamic AGM 105Ah 020 stop start battery. I fully charged it before fitting (on AGM mode on my smart charger). All good yesterday, no faults. Started it today, exactly the same fault appeared. I cleared the code, and then started driving and the gear symbol reappeared while driving. It was still shifting fine, so I carried on driving. When I got home, I put it in park and left the engine running while I went to get the laptop. As soon as I opened the door, I got the message that it thought it was still in gear. When I looked at the measured values in VCDS, it was showing as a fault with the selector module again, so I am now thinking it could be the wiring loom to the gearbox with an intermittent fault. I’ve read online that the transmission cooler valves can leak and get into the wiring loom, giving the faults I’ve experienced. https://forums.ross-tech.com/index.php?threads/32213/ https://static.nhtsa.gov/odi/tsbs/2013/SB-10053889-6593.pdf

I use VCDS Steve. This was the sticker on the top of the new battery, but I could not see any of the side stickers to get a brand. The invoice from the seller didn’t indicate a brand either. Out of interest, do you know what brand the OEM Audi batteries are? I’ve read Varta, but obviously I didn’t see the original battery to confirm.

Thanks Steve, I had wondered this myself. I did code the new battery to the car as the dealer hadn’t done it, but it didn’t have a BEM code on it so I had to guess the code. I was told as long as the code changes, this resets the adaptations, but I could not see the brand of battery when I looked under the seat so have no way of knowing if it is decent or not. I’ll pull the battery out and have a look but I doubt it’s a top quality one. The symptoms certainly point to being voltage related that’s for sure. I’ll order a decent new battery anyway and give it a go I think. Cheers

Hi everyone, I have owned my 2012 4L Q7 for around a month now and love it to bits. I have a really frustrating intermittent electrical problem and I'm hoping someone can point me in the right direction. I'm not an idiot when it comes to electrical problems on cars and have my own diagnostic gear, but I'm by no means an expert with the Audi Q7. I'm also an electrical/electronics engineer by trade, so I like to think I can have a decent stab at diagnosing things, but this has me a bit stumped. I bought the car from a dealer, who put a new stop/start battery on the car before I collected it, and that is when these issues started (although that could be a complete coincidence). 75% of the time when the car has been stood overnight (it does not normally do this if the car has been stood for around 8 hours in the day when I'm at work), when I turn the ignition key to the first position, I get a white small gear symbol on the display (see photo). If I then start the car, it will not let me come out of park. If I don't start the car and turn the ignition off and back on again, it is fine. If I start it and turn it off and on again, it is fine. I did fault code scan the car when it had the gear symbol on the display, and it returned 3 fault codes as shown in the first attached log file. Now this had also started happening to the dealer before I collected the car. His local transmission specialist diagnosed it as a faulty transmission selector module, and replaced it with a brand new one at a cost of around £500 to him (I have the invoice). This did not happen again until a few days after I got the car home, and now it happens again most days. If this was the only fault, I could probably live with it TBH as it isn't that inconvenient, albeit a bit frustrating. However, on 2 occasions it has turned into a bigger fault. On these occasions, when the ignition is turned to the first click, I get a large yellow gear symbol indicating a transmission fault and reduced functionality. When I fault code scanned the car with this fault standing, I got many fault codes with many different ECU's as shown in the 2nd attached log file. These fault codes mostly seem to indicate intermittent communication faults between different ECU's. Until these faults are reset with my laptop, I get reduced functionality on many things, and the car is unusable. I am having to carry my laptop around with me in case this happens when I am out. This one is obviously more of a concern, and my thoughts are that it is definitely connected to the first fault. I am thinking rather than it being a genuine fault with the transmission, it could possibly be a communication issue between the ECU's, possibly a faulty main ECU, possibly a faulty transmission ECU, possibly water ingress, or possibly damaged wiring. Then there is also the possibility it is connected to the replacement of the battery? I did recode the new battery to the battery control module to reset the adaptations when I first got the car, so it's unlikely to be anything to do with that. Can anyone think of a good place to start looking? I know these cars can suffer water ingress around the ECU's under the seat due to blocked drains, so I'm going to look there at the weekend as a starting point, but after that I'm struggling. The problem is that everything resets just fine and then remains fine until it has been stood overnight. Any help or advice would be massively appreciated, and if any of you are local to the Chesterfield area and need your car scanning, just ask. Thanks in advance Andy Log File 1.txt Log File 2.txt