Just got a 2007 TDV8 with a "Check Rear Fog light" message on dash, and rhs rear tail/fog not lit. Indicator, upper tail light, brake light working fine.

As only one side assumed simple bulb replacement, but have checked bulb and it is definitely fine.
Connectors look clean, wiring to lamp unit looks ok. All completely standard, ie no LED conversion or any other lighting upgrades.

Any ideas what else could cause this? Presumably these aren't individually earthed?

I know also have a check sidelight message on dash which appears to be front LHS, haven't checked bulb yet but suspect it is fine.

After a bit more searching I am beginning to think this might be an LCM issue, does that make sense to anybody?

On one side, I bought a Chinese replacement and nothing. At that point I started thinking its the wiring so I took out the taillamp and cleaned the wires, checked the prongs.

That worked, but realized I had the wrong bulb! So ended up ordering a very expensive LR fog light bulb and that solved all the problems 2008 HSE B. Grey
Overfinched
NavTV retrofit

Unfortunately in my case it is definitely not bulb. to triple check I swapped them from side to side and still have same problem on RHS whilst LHS works fine.

I have a vague recollection the front / rear lights are fused on diagonal corners - if the front side light is also out on the diagonal side, may be worth checking relevant fuses if not done so already.

I may be completely mis-recalling this however! Jonathan

2010 L322 5.0 SC Autobiography Black
2007 Defender 90 XS Hardtop

Thanks, didn't know that, but fuses are fine, checked them, and other functions covered by same fuse fine. Plus front LHS sidelight fault is intermittent.