Suddenly I’ve noticed that the right side brake light on my 1988 Vanden Plas no longer works when the ignition is off. At first I thought the bulb was out, but I found that it worked when I turn the ignition on. Should the brake lights work with the ignition off? The left side does. What should I check as the problem?
My car’s steering wheel is on the left side.

 

Update. I just checked and the right side brake lights are now working when the ignition is off. Hmmmm?

 

Hi Ernest,

That's a strange one. Check the wiring diagrams to see what difference there may be between power supply to the right brake lamp with the ignition off and on. You can download the Electrical Guide here:

Jaguar XJ40 Electrical Guide 1988-1989

Cheers,

Don

 

Thanks for the guide Don. I will check it out.