Tail lights and fog lights are not working
- Thread starter CharlieNeil
- Start date
Good - you're in the right place then.
Assuming you have halogen lights and not LED's
The left rear tail light passes through a light green connector pin 9 under the passenger seat. The wire is grey with a black trace. It then goes on to pin 3 on the light cluster
The fog light passes through a light green connector pin 4 under the passenger seat. The wire is grey with a white trace. It then goes on to pin 1 on the light cluster - Note this may not be present on both sides.
The right rear tail light passes through a light green connector pin 7 under the passenger seat. The wire is grey with a red trace. It then goes on to pin 3 on the light cluster
Use a multimeter to test for +12v at the light cluster between the wires/pins described above and the brown wire pin 4.
If you have no voltage here, move back to the green plug and test here. There probably won't be a brown wire through the connector under the seat so you'll need to use the earth stud in the floor instead.
Check the green plug for signs of corrosion and give the contacts a good clean if they appear tarnished.
Report back with you findings.
The left rear tail light passes through a light green connector pin 9 under the passenger seat. The wire is grey with a black trace. It then goes on to pin 3 on the light cluster
The fog light passes through a light green connector pin 4 under the passenger seat. The wire is grey with a white trace. It then goes on to pin 1 on the light cluster - Note this may not be present on both sides.
The right rear tail light passes through a light green connector pin 7 under the passenger seat. The wire is grey with a red trace. It then goes on to pin 3 on the light cluster
Use a multimeter to test for +12v at the light cluster between the wires/pins described above and the brown wire pin 4.
If you have no voltage here, move back to the green plug and test here. There probably won't be a brown wire through the connector under the seat so you'll need to use the earth stud in the floor instead.
Check the green plug for signs of corrosion and give the contacts a good clean if they appear tarnished.
Report back with you findings.
Also, just read your battery has run flat and you charged it in situ. Before you do any fault finding, disconnect the -ve from the battery and leave it off a few minutes. This will reset the BCM. This may clear your fault.
Looks like we might have sorted the problem. Using the multi meter we realised the problem was between green junction box under passenger seat and rear light clusters. So we looked into the spot light 50 mm holes and noticed damaged and cut wires. Also the VW door lights at the rear never worked and their was another cut thin wire here. Bridged all wires then tried lights and rear cluster on the right worked fine tail and fog but nothing on the left had to leave it at that will pick the job up tomorrow also the battery was flat again with all the testing so it’s on charge overnight for tomorrow but getting close. Thanks again everyone for all your help
The story continues, I've cut and bridged all damaged wires (I think) in wiring loom that passes along edge of passenger side of pop top to the rear of the van. Got the tail lights working on both sides BUT only 1 rear fog light works on the right drivers side (I've checked bulb and fuse). I've been on this for about 2 weeks off and on so was prepared to live with 1 rear fog light not working. BUT I went out in the van today and I have 2 dash warning lights on see image below. I think these might be damaged wires again in the same loom but if anyone knows what colour wire I'm looking for this would help. I have also done a battery reset where positive and negative touch for 15 mins but sill the codes show.
It's normal for some vans to only have one fog light, even though the bulb might be present in the cluster that's not working. The photo you posted of your light cluster wiring further up the thread shows no wire present in pin 1 so you only have one fog light on your van.
An ABS speed sensor could be causing the warning lights your seeing. The rear sensors pass through the brown connector under the passenger seat, I'm not 100% but think they follow the same route to the back as the lights.
Rear Left speed sensor is a black wire and a green wire
Rear Right speed sensor is a brown wire and black wire
It might be worth getting Carista to scan your van to find out exactly what the issue is.
An ABS speed sensor could be causing the warning lights your seeing. The rear sensors pass through the brown connector under the passenger seat, I'm not 100% but think they follow the same route to the back as the lights.
Rear Left speed sensor is a black wire and a green wire
Rear Right speed sensor is a brown wire and black wire
It might be worth getting Carista to scan your van to find out exactly what the issue is.
Thanks so much Deaky, I would never have thought only one fog light but now you mention the wiring your right, I would have spent days looking for that. I will take a look for those other 2 wire for the ABS speed sensor is the "slippery road" looking icon the same as the speed sensor? Also who are Carista?
Cheers again Neil
How did the wires behind the lights get damaged? have you just had a pop top fitted?
It’s a strange one all lights worked after the pop top fitted and picked up. Week or so later I fitted 50mm spot lights that I had to drill out. But the damaged wires are between the 2 holes I drilled, so I’m thinking it must have been a screws from the pop top fitting.¯\_(ツ)_/¯
I also cut out a rectangular hole to fit the VW door light that was originally in the roof, but again the wires were 8inches from these cuts
Just checking I haven't made a schoolboy error in bridging these wires along the pop top to the rear of the van. 1 or 2 of these wire were very thin and I never had this very thin wire so have used thicker lighting wire would this be too thick and disturb the current passing through it?
If they are twisted pair (orange/brown or orange/black) they could be canbus wiring but I don't recall any modules at the back that are on the canbus.
At least two of those wires in the photo you’ve sent match what I posted ten posts or so above - they go to the rear light cluster.
Thanks guys I’m going to work on it tomorrow I’ll let you know how I get on. I’m off to the NEC camper van show today
Both ABS (Anti-lock brake system) and ESP (Electronic stability program) rely on data from the rotational speed of each wheel, hence if one or more of the speed sensors is not working an error will occur in both systems.
Carista is a dongle that plugs into your ODB port under the dash and will read error codes and allow you to change certain settings. Carista OBD2 App | Diagnose, customize and service your car
Yes it looks like only 1 fog light who'd have thought. Everything there in the cluster of lights to work but no wire. Might put power to the other fog light at a later date. Now for the 2 warning lights on the dash
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