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Somebody stop me!
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Discussion Starter #1 (Edited)
Afternoon all.
Since my pop top was fitted in my 2012 t5.1 I’m having some strange issues with the rear lights on the drivers side only. They have done several odd things from fog on all the time with the van off to fog flashing with indicator on the drivers side. I have had the roof removed at vast expense to inspect the loom for damage and it checked out ok, towing electrics were spliced in the roof wiring which was removed as a precaution at the same time. I have had an electrician look at it and they can’t find the fault either. Today I cleaned the contacts under the passenger double swivel with the battery removed and shorted the battery terminals to reset the bcm and the issue still remains. Fog flashing with indicator passenger fog or brake light on with headlights and bulb warning light if I switch on the rear fog with the indicator. I’m getting the code 00968 - right turn signals short to b+ But am beginning to run out of ideas. Has anyone had a similar issue to this before and managed to solve it? Any help would be appreciated, nowhere is open and I need it fixing ASAP as I need the van for work.
 

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Somebody stop me!
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Discussion Starter #3
Thanks for the reply :) Presumably its the earth is going to the bolt behind the rear panel, if it is this one it’s clean and the wires going to it are absolutely fine. The electrician tested the earths and said they were good.
 

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Somebody stop me!
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Discussion Starter #5
I don’t know what exactly he did and where, I think it’s best I check them both for good order. New symptom I didn’t pick up on yesterday, the fog light is on with the headlights on the passenger side. The more I think about it the more I think the issue is the bcm as the faults seem to vary daily.
 

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140 DSG Shuttle SE full Camper
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the fog light is on with the headlights on the passenger side.
If that's the front fog light as there isn't a passenger side fog light at the rear, it may have the cornering function activated in which case that could be correct. Try turning the steering with the headlights on & see if a fog light is on with the way the wheels are pointing or the side the indicators are on.
 

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140 DSG Shuttle SE full Camper
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It must be brake light, there's no wiring to the near side rear fog light even though there's a bulb holder probably with a bulb in it. All the rear lamp wiring goes via plugs under the passenger seat, I'd test each wire out from there to the rear clusters, if OK temporarily connect a load of bulbs under the seat and see what gives. If you can't manage that take it to a decent auto electrician, not a domestic sparks as they won't understand auto electrics.
 

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Do T5's have a printed circuit type thingy in the rear cluster Jimmy? (Normally 1mm galvanised steel) If so have a look at that for corrosion Pal. This used to be a common fault on old fords from the 90's. Just an Idea from the T4 forum. :D
If not just Send me back (Cabin fever) I'll go back to annoying my wife.
 

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Somebody stop me!
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Discussion Starter #10
Do T5's have a printed circuit type thingy in the rear cluster Jimmy? (Normally 1mm galvanised steel) If so have a look at that for corrosion Pal. This used to be a common fault on old fords from the 90's. Just an Idea from the T4 forum. :D
If not just Send me back (Cabin fever) I'll go back to annoying my wife.
they do but both sides are in good shape with no water ingress. Everything looks in place which is why I’m struggling so much. There is probably an easy solution on this I just haven’t found it yet.
 

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Somebody stop me!
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Discussion Starter #11
It must be brake light, there's no wiring to the near side rear fog light even though there's a bulb holder probably with a bulb in it. All the rear lamp wiring goes via plugs under the passenger seat, I'd test each wire out from there to the rear clusters, if OK temporarily connect a load of bulbs under the seat and see what gives. If you can't manage that take it to a decent auto electrician, not a domestic sparks as they won't understand auto electrics.
I think you are right, must be a brake light. I took the van to an auto electrician and to be honest I didn’t get anywhere with them. I have been recommended another mobile guy who does work on a lot of vw’s but I’m reluctant to spend out on it to get another nil report. Basically I’m £500 in and the fault is still at large and the pot is diminishing rapidly :-(
 

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Special Rapporteur
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Fog flashing with indicator passenger fog or brake light on with headlights and bulb warning light if I switch on the rear fog with the indicator.
Symptoms of this type are almost always caused by earth problems. It's hard for a faulty BCM to cause these symptoms because it has no control (typically - there are a few exceptions) over the earth connection.

So my plan of attack would be to have the offending lamp assembly hanging off the vehicle and test the voltage of the parts that should be at earth while the problem is occurring.
 

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140 DSG Shuttle SE full Camper
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Your OP originally said you had a problem with the drivers side only but now it seems it's both sides. There's only one brake light cable going from under the passenger seat to the back to feed both light clusters, so to only have one brake light on at certain times & not others and with the other spurious faults you've got should narrow down where to look, as previously stated a few times it's probably an earth fault somewhere.
 

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Hi All, Newbie to the site here. Just reading through the list of faults I would offer the following advice. It does sound like an earth fault with the cluster. Have the bulbs been checked? I say this as on the rare occasion a bulb can fail internally and cause weird shorts. Although the earths have been checked - to what degree - has a resistance check on the actual cable to the body been checked? The cable may look good but could have corrosion to the actual wire inside the outer sleeve. Try a separate earth lead from cluster to body and see what happens. As someone also mentioned has the circuit on the cluster been checked? One of my clusters on my dare I mention Mondeo had shorted out between the galvanised tracks - not by much but enough to cause strange lighting of the bulbs.
 

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Somebody stop me!
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Discussion Starter #16
Well it seems I have plenty more testing to do next week, I will get my meter out and get cracking. I really hope it is as simple as a earth fault. Out of interest, does the loom from the near side run under the back of the van in a crossmembers somewhere? It will save me removing the under gubbins to check.
 

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140 DSG Shuttle SE full Camper
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Out of interest, does the loom from the near side run under the back of the van in a crossmembers somewhere? It will save me removing the under gubbins to check.
It runs inside over the top of the tailgate. Wasn't it checked when the poptop was removed? 😲
 

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Want Electrics? Go Wildebus!
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Ref the brake light on with the headlights ... something that can be worth checking is if the correct rear bulb is fitted. It needs to be a P21/4W IIRC, rather than a P21/5W one. A subtle difference, but the P21/5W has differently located connection pins at the base and it is possible to fit that bulb if you push hard enough but the result is the 21W portion of the bulb can come on instead of the 5W.
Essy one to miss as the P21/5W is a much more common bulb and if the original blew, one of these may have been fitted inadvertantly.
 

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Somebody stop me!
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Discussion Starter #19
Do T5's have a printed circuit type thingy in the rear cluster Jimmy? (Normally 1mm galvanised steel) If so have a look at that for corrosion Pal. This used to be a common fault on old fords from the 90's. Just an Idea from the T4 forum. :D
If not just Send me back (Cabin fever) I'll go back to annoying my wife.
continuity check done with bulbs removed and bulbs checked. All ok. Thanks for the suggestion at least


It runs inside over the top of the tailgate. Wasn't it checked when the poptop was removed? 😲
they removed the rear part of the frame so I would say they checked it. Thanks for the info, no need to remove the spare wheel and under trays now t:


Ref the brake light on with the headlights ... something that can be worth checking is if the correct rear bulb is fitted. It needs to be a P21/4W IIRC, rather than a P21/5W one. A subtle difference, but the P21/5W has differently located connection pins at the base and it is possible to fit that bulb if you push hard enough but the result is the 21W portion of the bulb can come on instead of the 5W.
Essy one to miss as the P21/5W is a much more common bulb and if the original blew, one of these may have been fitted inadvertantly.
Hit the nail on the head buddy, totally wrong bulb fitted, one problem off the list.
 

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Somebody stop me!
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Discussion Starter #20
New bulb fitted same symptoms with the exception of the sidelights now working as they should, thanks Hoovie. Family time for the rest of the weekend but will look at the earths next week.
 
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