Rear Foglights will not work C5 2001

[jmd]

I've son has had his C5 for the past seven years. Had test carried out recently and it failed because his rear fog-lights aren't working, the fronts are fine and the warning lamp lights on the dash are working but no rear fog lights..
Fitted 2 new bulbs, checked the relevant fuse, (in fact all fuses) all o.k -but still no rear fog-lights. I have looked around for a relay, which indicates from the clicking sound produced when the switch is turned on/off that a relay is situated under the existing (interior) fuses inside/under the glove box compartment .
I removed the glove-box, and can only see a PCB in this area, where the clicking is produced.
Has anybody had this problem, or offer any advice on my problem. All other rear lights are working.

[Gibbo2286]

In my experience relays are rarely the problem, I'd be tracing the wiring loom from the lamps forward, looking for damaged wires or corroded connectors.

[jmd]

All other rear lights are working, which makes me wonder is it a faulty relay somewhere or a faulty BSI or ECM unit. Probably need to get it on a diagnostic unit.

[Homer]

Just a thought, does it have a towbar?

Some towbar electrics are designed to isolate the foglamps when they have something plugged in, could be playing up.

[jmd]

Thanks Homer. Yes it has a towbar. Never used during our ownership though

[jmd]

Thanks Homer, & Gibbo. Towbar wiring was the problem, connections or plug gone bad. Disconnected tow-bar wiring & fog-lights working perfect.