Post by crash223 on Aug 21, 2021 14:19:14 GMT
Hi all,
I recently bought a 2013 Passat TDI and it has been nothing short of a nightmare for the last 60 days.
I would consider myself a relatively experienced technician, and a very experienced mechanic. This issue has me lost for explanations.
The issue:
My brake lights (outer lights/positioning lights) do not come on when the brake pedal is pressed. Direction signals work (bulb is shared) hazards work, 3rd brake light works (above the rear deck).
Cruise control and shifting a works as expected, brake switch mounted blow the reservoir functions as advertised.
But the brake lights themselves will not come on at all either as running lights, or when braking.
What I've tried:
I've swapped out all lights on both assemblies (inner and outer). I've visually inspected the wiring looms and traced the wires back from the lights. Inspected ALL fuses on the car because VW have no labeled diagrams on the owners manual and no online diagrams seem to align with my vehicles fuse boxes. Attempted the the lights on through OBD 11 (same story 3rd comes on and that is all)
The 09 module/BCM is telling me I have a short to B+ but I know this is impossible as it's a 3 wire system and the direction signals function, in addition to having checked the loom.
I'm beginning to suspect a coding issue. I verified the coding is identical to the long coding present on the module when I first scanned the car. That did not fix the issue, yet it's still my suspicion this is what is causing the problem. If anyone has coding suggestions for my BCM please drop them here. I'm not a computer technician and they HEX, BYTE, and decimal stuff is not second language to me. I can match up what I see, but language used to describe each HEX/Bytes purpose isn't really that great imo.
Any help would he appreciated.
Thank you!
-Todd
I recently bought a 2013 Passat TDI and it has been nothing short of a nightmare for the last 60 days.
I would consider myself a relatively experienced technician, and a very experienced mechanic. This issue has me lost for explanations.
The issue:
My brake lights (outer lights/positioning lights) do not come on when the brake pedal is pressed. Direction signals work (bulb is shared) hazards work, 3rd brake light works (above the rear deck).
Cruise control and shifting a works as expected, brake switch mounted blow the reservoir functions as advertised.
But the brake lights themselves will not come on at all either as running lights, or when braking.
What I've tried:
I've swapped out all lights on both assemblies (inner and outer). I've visually inspected the wiring looms and traced the wires back from the lights. Inspected ALL fuses on the car because VW have no labeled diagrams on the owners manual and no online diagrams seem to align with my vehicles fuse boxes. Attempted the the lights on through OBD 11 (same story 3rd comes on and that is all)
The 09 module/BCM is telling me I have a short to B+ but I know this is impossible as it's a 3 wire system and the direction signals function, in addition to having checked the loom.
I'm beginning to suspect a coding issue. I verified the coding is identical to the long coding present on the module when I first scanned the car. That did not fix the issue, yet it's still my suspicion this is what is causing the problem. If anyone has coding suggestions for my BCM please drop them here. I'm not a computer technician and they HEX, BYTE, and decimal stuff is not second language to me. I can match up what I see, but language used to describe each HEX/Bytes purpose isn't really that great imo.
Any help would he appreciated.
Thank you!
-Todd