Hi All,

I am new to this forum, and i'm writing this to see if anyone can help me diagnose a problem with my car, an Audi A4 B7. The problem i have is that the rear number plate lights are both not working. I previously had LED bulbs in them and randomly they both shut off, which is unusual because if a bulb is bad the one that's bad will turn off. I changed the bulbs for some original halogen ones and still nothing. Only when i start the engine they turn on and the boot must stay closed to keep them on, as soon as i open the boot they both turn off and refuse to come on. Then if close the boot, turn the lights off and on again from the inside switch, absolutely nothing. I then looked for a fuse and couldn't find one, i removed the comfort module fuse (20amp yellow), and reinstalled it to have the bulbs turn on again. If i turn the engine off and return later on they don't come on, and i need to remove the fuse and reinstall the fuse again to turn them back on. Also if i swap the bulbs for different ones they work, but the same problem persists they turn off when the engine turns off and don't come back on.

I've had this problem for a couple of weeks, and wondering if anyone is having the same problem or knows a way round this, as the MOT is also coming up soon.

Thanks Suhail

Hello Suhail,

More a couple of ‘may be s’ rather than a claim to fixing the problem:-

Remove the fuse, then spray some genuine contact cleaner (should be available at your local motor factors) into the fuse socket and wiggle the fuse a few times, in a attempt to ensure the contacts in there are good and clean. Test for continuing problems at this stage.

If this doesn’t solve it then peel back the flexible rubber harness covering around the harness linking the body to the tailgate, and inspect each wire for damage or splitting. It is not uncommon for cables to split due to flexing when the hatch is opened and closed - most of the damage actually occurring during the cold winter months when the cables are less flexing. 

The above are meant as eliminating simpler possibilities before moving on. 

Perhaps you could let us know how you get on. 

Kind regards,

Gareth. 

Cheers Gareth. I'll take a look at these.