Rear fog light not working

[Nigelgta]

A couple of days ago got a 'check rear fog light' warning on the dash of my 2009 Granturismo 4.7S. Sure enough, checked and rear left side not working. Bought a new bulb, swapped over, but still not working. So, since I've swapped the 3 bulbs I now have between the 2 rear fog lights and even swapped the 2 plastics bulb holder units over. Every time the rear right works, the rear left doesn't. So, it would seem that it's not the bulb, nor the plastic bulb holder unit. It can't be he fuse can it, as the manual seems to suggest both rear fogs work off the same fuse.? Any ideas???
Cheers, Nigel

 

[Megaman]

Hi,

I'm french guy and i have the same problem as you on my QP5 2008. I don't find the problem. I have test the ground, clean ground on read and front ...
I have test the resistance at the output of CPL and the base of the fog bulb and i have a resistance. I don't undestand why i don't have 12V.
Have you got the same analyse ?

 

[StuartW]

It could be damage to the cable that runs in the plastic casing next to the boot hinge. They can get brittle and start to deteriorate, I had it in my GTS but affected the number plate lights - I assume that the fog light cable follows the same route to the rear of the car?

 

[Megaman]

No. I remove the carpet in the boot and the cable come directly from the CPL. The cable who feed the number plate lights is not the same.

 

[Nigelgta]

Hi, I haven't solved mine yet. I've got resistance at both the bulb and the bulb holder, but seemingly no voltage at the connector that connects from the loom to the bulb holder. I was going to have another look over the next couple of days, taking the trunk liner off to see where the fog lamp cable goes to. I suspect a broken wire and was thinking it could be in the rubber trunking between the trunk lid and the car, as Stuart suggests. That's a very common place because of the movement on the wires every time you open the boot.

 

[Megaman]

may be. Give me some news.

 

[Nigelgta]

So, explored further today and, as suspected found a broken wire in the wire trunking connector between the car and boot lid. Quite an easy fix then, with a bit of soldering and heat shrink, but getting the wire through the rubber trunking was a real pain. All seems sorted, both fog lights working again and no fault messages on the dashboard. Took just over an hour to sort. This was on my Granturismo, don't know if the QP has the same rubber trunking with wires from the car into the boot lid.

 

[Gazcw]

A couple of days ago got a 'check rear fog light' warning on the dash of my 2009 Granturismo 4.7S. Sure enough, checked and rear left side not working. Bought a new bulb, swapped over, but still not working. So, since I've swapped the 3 bulbs I now have between the 2 rear fog lights and even swapped the 2 plastics bulb holder units over. Every time the rear right works, the rear left doesn't. So, it would seem that it's not the bulb, nor the plastic bulb holder unit. It can't be he fuse can it, as the manual seems to suggest both rear fogs work off the same fuse.? Any ideas???
Cheers, Nigel

Had that on my Alfa. Cable into boot was shot somewhere and I couldn't be bothered to fix. Because the rhs worked it never failed the MOT.

 

[BennyD]

What’s behind you doesn’t really matter, unless it’s Hodroyd!

 

[CatmanV2]

So, explored further today and, as suspected found a broken wire in the wire trunking connector between the car and boot lid. Quite an easy fix then, with a bit of soldering and heat shrink, but getting the wire through the rubber trunking was a real pain. All seems sorted, both fog lights working again and no fault messages on the dashboard. Took just over an hour to sort. This was on my Granturismo, don't know if the QP has the same rubber trunking with wires from the car into the boot lid.

Had that on my Alfa. Cable into boot was shot somewhere and I couldn't be bothered to fix. Because the rhs worked it never failed the MOT.

So so frequent.

C

 

[Megaman]

for mine, i saw that was a connector behind the rear seat. I must see if the wire wasn't cut.

 

[Ryandoc]

I recently had some wiring repairs done to mine for bulb on the rear not working. I don’t have full details other that that but this was in the last 7-8 months

So wiring faults can happen

 

[Megaman]

no pb between the bulb and the rear connector. I ll check between CPL and rear connector. It's not easy.