Rear view mirror electrical Issue - 2014 A8L 3.0 TDI

   #1  

mattysdaddy

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I realize that this may be a long shot but I am wondering if anyone has experienced an issue where your rear view mirror electrics seem to stay on after the car is switched off. The compass stays on, as does the green auto dimming indicator.

My wife and I have identical A8L's and her car seems to switch off the mirror functions when the key is switched off. I have developed a one to four amp parasitic draw and my battery will discharge overnight if I do not have a power supply connected up to the car.

I recently replaced the battery with an H9 and recoded using VCDS. I tried to put the car to sleep and measure milliamps across each fuse and was unable to find a substantial draw. Has anyone had good luck using an "Amp Hound" device?

Any suggestions related to the mirror staying on would be appreciated. I can post a full autoscan this evening.

Thanks! Joe
 
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SaVAGeSoot

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I tried to put the car to sleep and measure milliamps across each fuse and was unable to find a substantial draw.
So are you suggesting that your suspect "rear view mirror" is running off an unfused circuit? :confused:
Or are you saying your actual draw is coming from a different "live" component which is also unfused?
 
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mattysdaddy

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The rear view mirror is definitely fused. I can pull the 5A fuse in the trunk associated with the rear view mirror and the power goes off. No compass or green light auto dimming indicator with the fuse removed. With the fuse pulled, I do get an error indicating that my headlight assist function is unavailable. This error is more annoying than the mirror functions staying on. Why the mirror is staying on with the car switched off is beyond my comprehension.

I have some sort of parasitic draw even with the mirror fuse pulled that varies somewhere between 1-4 amps. I have been unable to locate this parasitic draw but I will continue to look for it.
 
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SaVAGeSoot

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I can pull the 5A fuse in the trunk associated with the rear view mirror and the power goes off.
So, since you've located its fuse, if you don't measure a significant draw across IT when you're doing your parasitic draw tests, that must NOT be your issue.
Why the mirror is staying on with the car switched off is beyond my comprehension.
No clues in the WD?
 
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   #5  

SaVAGeSoot

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Did you look at the anti-dazzle relay? Should be #5
 
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mattysdaddy

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I did not. I certainly will. Can I pull this relay to see if my mirror electronics go off or my parasitic load goes away?
 
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