Hi all, my MK2.5 focus has developed an electric problem. When I switch on the ignition and turn on the lights the brake lights and dash lights come on.Could this be an earthing problem. I have no idea where to start looking.
Regards,
johnno

 

Sounds like its back feeding , check the bulbs, and check where the rear lights earth in the boot of car, might have to remove some trim.

 

Hi GVK, thanks for prompt reply, Had a bulb replaced when in for MOT, Will check tomoz for defect bulb.
regards
Johnno

 

Aha! Bet they have put a single filament bulb in a twin filament socket....

 

Well GVK, you were spot on, took it back today and they confirmed what you had suspected. they had indeed put a single filament bulb in a twin filament brake light socket. Many thanks again for your invaluable knowledge.

 

Won't be the first or last time someone has done it! Glad it was a simple fix.