BCM short to ground Help !!!!

[The_Lad]

I have on and off been having issues where the interior lights in my van stop working and i need to reset the fault with carista where they will work again for a while

03434 - Output terminal 30G for interior light: Short circuit to ground
Freeze frame :
Priority: 3
Malfunction frequency counter: 9
Unlearning counter: 147

So firstly it has occurred 9 times? and it will clear itself if it sees 147 ignition cycles without a further fault? but the lights havent worked for ages so im not sure about this?

Any way i need to understand where the fault is likely to be as i have done some wiring years back which has been fine and i dont think i have used anything that could even potentially cause this.





Above diagram show what i have done, for my rear lighting i have taken a single wire from the plug in the ceiling which appears to be a timed ground (im presuming that this wire is not pin 30g from the BCM as i cant short a ground to ground) i run that timed ground to a switch where i select either that ground or a perm ground to the light which also has a perm live from the leisure battery and this has worked fine for years.

So now im thinking maybe the fault is actually in the OEM wiring to the VW cab lights? do the cab lights take a feed from BCM pin 30g? what color is this wire and where does it run round the van?

Can anyone here help me with info on

BCM Pin 30g wire color?
BCM Pin 30g where does this wire go
Any ideas on how to troubleshoot this issue?


Cheers
Justin

 

[paddy26]

I'd suggest to remove your connections to the bcm(return to factory spec)and test to see that the error is gone.
Once that's working you can look to add the cargo lights.
What colour bcm wires have you connected to?

 

[The_Lad]

Well I’ve tried by switching the switch to the off position so I’m not passing the neg timed feed into my circuit and the lights still fail.

I think it is the brown/red wire I have tapped into in the rear and I don’t think that is BCM pin 30g?

My feeling is that red/black is the BCM pin 30g wire and I’m not using that so that would indicate the issue is either in the cab lights or there is a short somewhere wherever that wire runs?

 

[Dellmassive]

some info on the LED wires here:

LED Interior Cargo Lights - How I Done It.

LED rear interior lights - How i done it. so a few have asked, so i though i would just list it here as a post so i could refer back to it in the future. The lights were purchased from The T6F shop over here > We were planning to do the carpeting at around the same time, but for the purpose...

www.t6forum.com

***************************************************************************************
Factory Non-LED 3 wire setup:

(brown) - earth point left a-pilar
(brown/red) - connection 1 main harness (BCM switched neg 0v)
(red/black) - positive connection 1 main harness (BCM timed +12v) ( 7.5A fuse 24 holder C)
****************************************************************************************

Factory LED 2 wire setup:

(brown/red) - connection 1 main harness (BCM switched neg)
(red/black) - positive connection 1 main harness (BCM timed +12v)( 7.5A fuse 19 holder C)

****************************************************************************************

 

[Deaky]

I don't think the BCM would detect a short to ground on the -ve switched brown/red wire. I'd say its the courtesy circuit +ve wire red/black that connects to pin 59 in the black connector on the BCM. Terminal 30G is the name VW give the circuit.

 

[The_Lad]

cool so does anyone know where the +ve red/blk wire runs in the van its from the BCM which is driver side dash? then i know at least 3 locations 2 in the roof in the rear and one in the cab to the lights

Thanks Deaky for confirming that term 30g is the red / blk wire

anywhere else?

1. Remove front oem cab lighting completely and see if the issue is resolved
2. trace the wire through the entire van until i find a short (this sounds difficult)

 

[Deaky]

It runs across the dash and through the coupling points under the glovebox. I think it’s the beige one

 

[The_Lad]

Ah ok so I’m looking for a red/blk wire from the BCm into a beige plug then I guess it somewhere splits into multiple wires