2008 C4 Reg Plate Lights

[RJE]

Hello everyone!

 

Right, not got much hair left to rip out!

 

My C4 has decided that it only wants one reg plate light working..been using LED's for a while now with no issues.

 

The O/S light just doesn't want to know.. Tried different bulbs (led and standard), swapping the holder with the other ect. not a bean!

 

So, out comes the multi meter.. Testing the wiring at the connector, I get 0.8v (taking into account the multi meters variance)

Now before I go all hulk on my rear bumper and remove it with clarkson engineering, is there a common fault? Trapped wiring somewhere? Fuse? (that is nicely hidden)

 

What route does the wiring take? Is it through the body or through the good old boot kid grommets?

 

Hope that actually made sense!

 

Rob

[paul.h]

According to the wiring diagram in the Haynes manual, both no. plate lights have the same 12v supply and earth wiring - so if one bulb is receiving 12 volts and has a good earth but the other does not have these, then the problem could be a corroded bulb holder or its wiring connections or a broken wire between the 2 bulb holders.

 

The first thing would be to access the back of a bulb holder - Haynes says to remove a holder without removing the bumper, push the holder to one side and then ease it out but this could damage the securing clip.

[RJE]

Hi Paul.

I have had both holders out. It was the connector to the holder where I got the readings.

 

So it's a case of bumper off and check back to where the loom splits?

 

Really should get myself a haynes!

[paul.h]

I would guess the loom splits at the good holder, if so you could possibly check it here or run a new wire from here without removing the bumper. You could do a meter continuity check between the 2 holders before disconnecting anything - so should have little resistance between the 2 +ve terminals and similarly between the 2 earth terminals if the wiring is ok.