Electrics: No Rear Lights

[XC70Bob]

Originally Posted by oldtimer1

That's great thanks I was looking at the board that is in the drivers footwell above the accelerator peddle, how do I access the board you point out.
really appreciate the help.

Colin.

The board image I posted is the CEM which is the board above the drivers peddles, the image shows a 2004 v70 CEM, if yours does not look like this then it may actually be a 2005 car.


2004 CEM


2005 CEM

so which do you have ?

[oldtimer1]

Its the 2004 one now sorted, I think the problem originated from plugging the caravan in I used an adaptor to get from 7 pin on the van to 13 pin on the car. I think the first time I plugged it in I got it wrong the brake lights also blow.
Thanks again for your help Tim.

[ShaneOmack]

Originally Posted by Missing Lincs

According to the diagrams I have there is only one relay for all the sidelights. It appears to be part of the Central Electronic Module which lives under the dash (drivers side for RH I think).
Does the instrument light up, if it does then the appropriate code is being generated by the car which would then point to the relay being at fault.
You could also check for fuses blown under the bonnet, there looks to be a 20A fuse which supplies the lighting circuit, there are two other fuses after the relay on the inside of the car, one for front lights and one for rear.
The main problem for you seems to be getting hands-on with the car?
Best of luck.

I have a C70 with the same tail lights inop. The dash lights also do not work. fuses are good however Im showing ground at the fuse when it should be power. i have yet to find a good wiring diagram to see what powers the fuse . Any help would be deeply appreciated. The car belongs to my recent ex. lol I know that sounds crazy bot I know how much it would cost for her to take it to a shop. I just don't have it in me not to try and help out.

[DJFish]

Hi all,
It turns out that I've been driving around for ages with only one tail light! So I thought I'd post this in the hope someone might find it useful.
I recently had an intermittent upper (of the pair) tail light failure which was usually solved by a quick tap, after a while I started ignoring it (and the dash warning message) as there were three others on the back of the car and there was never a good time to pop into Halfords for new bubs.

Then the other day I finally got around to it and realised that there was nothing on the right two bulbs.

The brake lights, indicators, fog, reverse and number plate lights all worked, but no upper or lower position or driving lights or led's, but only on the right hand side...
Curious....

So the fault finding began,
Having just wired in a subwoofer I was hoping I hadn't botched the wiring or broken a wire.

First thing I did was replace the iffy top left bulb, that seems to have stopped it playing up.

Next I swapped the bulb holders over left to right & vice versa.
That didn't help but at least proved all the bulbs were ok.

Next job, check all fuses which were all ok.

Next job was to check the tailgate wires, they were a little chewed up but I've taped them up and they'll live for a while longer before they need repairing properly.

Mine has the facelift fuse board/electronics module so no relays to replace.

Then I read somewhere about the car deliberately switching off one side in the event of a fault, so I got my cheapo fault reader and scanned the OBD port, there were no faults showing but I thought I'd clear them anyway, and lo and behold that did it, all four lights back on.
I now have four driving/parking/position or whatever you want to call them lights on and no more dash warnings.

Hope this is of some help to anyone with the same, seemingly common issue.

Cheers
Dave
2005 V70.

[DJFish]

Or maybe not…
Went over a bit of rough tarmac earlier, no offside position lights once again!
I’m getting fed up with this car…

[DJFish]

And another update.

I eventually traced the fault to a loose pin connector on the Delphi plug in the back of the rear electronics module that sits in the rear near side wing.
That’d explain why a knock on the light would sometimes fix it.
I probably damaged it myself when i installed my sub.
I took the pin block out of the locking cover and plugged it directly to the CEM/fuse board and wiggled each wire in turn.
The grey wire in position 5 would make the tail lights flash on and off with an audible click from the relay in the CEM.
So I dug it out of the block and replaced the connector, that seems to have done the trick.