Mechanics can’t help me- electrical problem

[CharlieRR]

Hiya! I’m in desperate need of some advice.
So I have a 2015, polo 1.2L.
Basically, when I turn the vehicle on it works fine, but when I turn my lights on, it comes up with a cluster of faults like bonnet, open window, wiper fault, check coolant, and stop start not working. The lights cut out for a few seconds the indicators stopped working, The horn and emergency lights nd Bluetooth turns off.
Went to the mechanics they plugged it into the machine. Came up with every problem. They then referred me to electrical Mechanic, He said he doesn’t understand and that it could be water damage but i don’t understand how it “be water damage “ They change the battery and body module still not working. The car runs completely fine even with these problems coming on. it just seems to happen when I turn the lights on.

[iichel]

Could you be more specific when this happens?
Engine on/off
When the low beam comes in
When only the parking lights come on
When only the high beam comes on
Same for fog lights with parking lights
Do you have led or halogen lights
What happens if you disconnect either the left or right headlight unit?

[CharlieRR]

I don’t know much the light have to do with it, my guess. But iv just noticed that when I’m driving to work in the dark they will turn off for a second. Come back on and then the cluster of warnings start. But when am driving home from work and I turn the lights off nothing happens and the drive drives fine. So that’s what makes me believe it’s the lights starting this problem. I have got videos but I don’t know how to post it on here . Thanks for getting back to me

[CharlieRR]

https://youtube.com/shorts/-kjVaeNBuko?feature=share [youtube] here is a video to show you what’s happening

[iichel]

I understand that you don't know but if you want us to help you, and point you in the right direction, I need more specific information.
That means you'll need to do some testing and pulling some plugs from your headlights in order to isolate the problem. We need to be systematic, guessing will not identify the issue.

So please go through all the conditions I listed and tell us what's happening.

[Maarten]

Can you post a VCDS log?

[Rbpoole]

Did you solve this? I have the same problem. Thanks

[Kev_Polo]

https://youtube.com/shorts/-kjVaeNBuko?feature=share [youtube] here is a video to show you what’s happening

Exactly as video shows I have same problem.
Turn on light with engine running / stationary or driving
Faults start with warnings in this order:
Rev counter flicks
VW logo appears as it does when ignition is switch on initially (This can happen a few times withing few seconds) then comes:
Wiper Fault
Engine bonnet open
Engine over heating

If whilst I have lights on and go over a ramp on road or bumpy road then the central locking on hatch back clicks open / closed

Garage had it for a week, initially I found similar case on internet, only happening with 2014 / 2015 Polos - This was said to be bad earth on left rear lamp cluster plug/socket
That has been checked, on both rear light clusters with no fault found, they sent me pics of both clusters and totally clean, now sign of corrosion.
They also checked and cleaned (using their words) earth wires on rear chassis. They thought it was solved.

When fault occurs it knocks out turn/indicators lights, stop/start function, wipers will only work whilst I hold down stalk otherwise they stop when I release stalks
Other things that don't work is main beam light don't come on even though blue bulb on dash shows on when I flash. Only dip beam is on.

Garage says that car is in 'limp mode' and requires a software update
Only other things to add is I replaced battery when issue started with a Bosch AGM battery
Can run all day without any faults / problems if lights, either side or dip are not activated

Today I need the car until Sunday, so returning it next week on Monday to garage

Thanks in advance for anyone who might have suggestions I can submit to garage.
Kev

[Kev_Polo]

I think this forum is a dead fish!!
Surely somebody has an answer

[ciclo]

I think the 6C is a very strange car, a Frankenstein type monster I would say.