Intermittent indicator problem

[Snapperseb]

Hello all,

 

While signalling left the other day my Octavia 3 beeped at me and flashed up a warning to check the left turn indicator signal.

 

Sure enough, the left door mirror repeater had stopped working.

 

I partly dismantled the mirror to get at the wiring, thinking it might be a bad connection or a broken wire. 

 

TLDR: it's working again, for now. BUT here's the thing: I found no bad connection, no broken wire (lots of wiggling to test), and nothing I did got the repeater working again. It just began working of its own accord. 

 

On further testing, and through further random cycles of working / not working, the voltage to the repeater was cycling 12v/0v as expected when it was working, and was showing either a constant 0v or a constant 8v when it wasn't.

 

I did switch to the Superskoda dynamic indicators a week or so ago, but they worked fine on installation and I've had no problems with the originals. I tried plugging an original indicator in during one of the repeater's not-working phases, and that didn't work either.

 

So it doesn't appear to be the indicator unit, or the connector, or the wiring in the mirror housing.

 

Am I looking at a potential BCM fault? It's the intermittent nature and the apparent randomness that's stumping me...

 

Thanks in advance!

[Snapperseb]

1 hour ago, Snapperseb said:

 

Am I looking at a potential BCM fault? It's the intermittent nature and the apparent randomness that's stumping me...

 

Having done a bit more reading, I'm beginning to think it's more likely to be a door control module issue, since it's only the mirror indicator that's affected on that side. I've sometimes had issues with door control modules on previous cars... usually water ingress of some kind.

Can anyone confirm that the signal for the mirror indicator comes via the door control module?

[PipH]

Check the wires in the rubber boot by the door hinge.

 

The wires might be fractured & making intermittent contact.