6R Rear lights, side lights and interior lights not working

[Marthool]

Hi can anybody help please?
The rear lights, side lights and interior lights on my 2013 6R Polo are not working. The bulb light on the instrument display is on, I have checked all the bulbs and all the fuses, could the fault be with the light switch or BCM? How can I test these? Is there something else I could check?
Anyone had a similar problem that could steer me in the right direction would be great thanks

[ciclo]

Check the condition of:

- Light switch. T17/16 wire.
- SB7 fuse.
- Headlight level regulator / dimmer. T6/3 <-> T6/5.

The fault is probably in the dimmer.

Once the corrective action has been carried out, the fault must be cleared with a diagnostic tool.

[Marthool]

Thanks for replying
- I have previously checked the condition on the light switch (taken apart) the wires also look ok. When turning on the dash and switch lights come on as well as the headlights and fog lights
- I have checked the fuse with a multimeter all ok
- With regards to the headlight dimmer / leveller the wires look ok and the dimmer works for the dashboard and switches and the leveller works for the headlights. Will there still be a fault with it? Can it be taken apart to be checked?
Where you have said the fault must be cleared with a diagnostic tool will that be for the lights to work again or just to clear the bulb light on the dash?
I also noticed earlier that the airbag light and tire pressure lights are staying on, will that suggest some other problem?
Thanks again for taking the time to reply

[ciclo]

Sometimes, even if corrective action has already been taken, stored faults must be cleared with a diagnostic tool to get the lights working again. Logically, the warning light on the dashboard will also disappear.

Well, the light switch, fuse, and dimmer appear to be working correctly.
Due to the new info you mention about the airbag and tpms warning lights, how is the battery status? maybe it's time to change it, ... or maybe a new charge would be enough.

[Marthool]

I have put the battery on charge today but it seems to be in good condition. I connected an obd device and cleared a fault code (forgot to note it down in excitement ) this has removed the tire pressure warning light. So it is just the bulb light and airbag light that remain on.
I have removed fuse 21 and checked that there is 12v which there is, from here does it go to the BCM? If so then where does it go?

[ciclo]

SB21-->T73a/66 -->in_BCM_out--> T3a/65 -->>> interior lights.


...Have you recently done any special/fun electrical installation?
E.g. Install LED taillights that ruin the electrical installation of the European 6Rs due to the resistances and other small 'electronic' boxes built into them which are only useful for the 6Rs manufactured for Chinese market.

[Marthool]

No not added anything like that, changed the radio March last year to a Sony using correct wiring harnesses but that is working fine. The interior lights stopped working first around Sept then the rear and side lights recently.

T73a/66? Is that the back of the fuse box? Do you know what colour the wires are?
Thanks again!

[iichel]

T73a/66 is pin 66 of the black BCM connector. SB21 is fuse 21 on fuse holder B (below the steering column).

[Marthool]

Is pin 66 going into the BCM? What would be the pin for output? Just so I can check for voltage to rule that out for the fault please

[Marthool]

Do either of you have a wiring diagram similar to this post
viewtopic.php?p=601011#p601011
But for the rear and side lights so I can find where the voltage drop is please

[iichel]

BCM pin (on connector A = black) 66 is the input, 65 (the next one) is the output

[Marthool]

Do you know where the wire from pin 65 goes to so I can test that please?
Also do you have a wiring diagram for the rear / side lights similar to this one for headlight switch pin:-
viewtopic.php?p=601035&sid=58f7e9533a97 ... a0#p601035

Thanks again for the help

[ciclo]

POLO 6R diagrams https://drive.google.com/file/d/0B2nv91 ... KxQGUiXrgA

You may need to request permission to view or download, do it, and as soon as possible it will be enabled and notified.

[Marthool]

Thank you Fernando, that’s some heavy reading for later!! Hopefully I will be able to get to the bottom of the fault

[ciclo]

With the invaluable help of Ross-Tech you have 2 video tutorials to understand VW diagrams in case you need it:
Part 1 of 2:
https://www.youtube.com/watch?v=jKnTjuSmwaE
Part 2 of 2:
https://www.youtube.com/watch?v=bMn0i-yHhSA

It's a little hard to understand at first, but it will be extraordinarily useful in many circumstances. Please take a first look at them for familiarization.

It must be taken into account that in many cases it is necessary to know how the inspected system works, which is either known or learned little by little, but it is not an obstacle due to not knowing it.

In any case, I will help you if you need help understanding the specific diagrams for your problem or for quick handling of the PDF file. Please feel free to ask any questions you need, I'm sure we will find the problem.

I think there is a short circuit or overload on signal 58 and the BCM acts accordingly...