8P Wing Mirror Indicator/Repeater Strange Issue - Grounding?

[swedeee]

Hi guys - first post. Use the search to no avail so thought it was best to ask in here

I bought a 2012 Audi A3 1.6 Technik in early April. It's been great so far, even for a base model (had use of an 09 1.8T A3 previously). However, a few weeks ago I started having a really odd issue with both wing mirror indicators;

• Either one of them will stop working completely, or at best flicker on slightly (never both dying at the same time!)
• This alternates between mirrors every few days, but the right one seems more afflicted
• Rear and front indicators have no problems at all
• When a single mirror indicator works, the speed and brightness of the indicator is completely normal
• No other electrical problems with the car at all (to my knowledge)
• No warning lights

Troubleshooting;

• The fact that this has happened to both mirrors at the same time, and the fact that they do work completely normally every now and again, makes me thing that wiring to the mirrors and the bulbs themselves are fine
• The front and rear indicators are fine and work perfectly when indicating and using hazards - making me think there is no problem with the relay
• Lack of other electrical faults makes me think the battery is absolutely fine
• The intermittent flickering of the mirror indicators when on makes me think it could be a grounding issue...

Any other suggestions? I am quite handy so keen to try sorting it myself before handing it to garage (it will not pass an MOT if the problem persists)

cheers

 

[NHN]

Check door hinge wiring for breaks, ideally try a new indicator if no obvious wiring issues.

 

[swedeee]

I have checked the door hinges - all seems normal.

I also find it hard to believe that it is a mirror wiring issue.. after 6 years since manufacturing, both miror indicators start playing up within a few days of each other? Very odd. Appreciate the input though!

 

[NHN]

Basics 1st bud, then get down & dirty.

 

[ch1z64]

Maybe a scan will throw up error codes maybe a short to ground . Best to find out

 

[swedeee]

Not a bad idea actually - much appreciated!

 

[ch1z64]

Not a bad idea actually - much appreciated!

Worth looking up the net if you don't understand what the term ( short to ground ) means

 

[swedeee]

Yep I have been swatting up on my electronics, it could definitely be a short to ground somewhere causing an issue. Just locating it is going to be a pain

I am going to clean all the ground points to begin with, followed by checking the current flow to the wing mirror. I can't find a ground point diagram for the audi a3 8p or a mirror wiring diagram either. Would anyone be able to point me in the right direction?

 

[ch1z64]

Yep I have been swatting up on my electronics, it could definitely be a short to ground somewhere causing an issue. Just locating it is going to be a pain

I am going to clean all the ground points to begin with, followed by checking the current flow to the wing mirror. I can't find a ground point diagram for the audi a3 8p or a mirror wiring diagram either. Would anyone be able to point me in the right direction?

There is a web site you can use for around £30 for 24hrs which gives you printing rights but you will need a hell off a lot of paper ( https://erwin.audi.com ) there u will find all the info you need about your car.

 

[swedeee]

spoke to a car electrics specialist the other day, he reckons it isn't a grounding issue if the wing mirror adjustment motors, window motors and central locking works ok - as in the 8P all those components get power from the same source. he says to change both wing mirror indicators - and thanks to a post on here ( https://www.audi-sport.net/xf/threads/wing-mirror-led-advice.169692/ ) it shouldn't be too tricky