400se earthing points

[CHJ]

Does anyone know where the earthing points are for the rear light clusters - particularly the brake lights and reversing lights?
I've have an annoying problem where the brake lights do not always work, and never work when the headlights are on, and the brake light fuse blows when reverse is engaged. I was hoping Dulfords were going to sort it out this weekend but they have just had to postpone, so I'm going to have another go myself. Given the car was MOTed by RT in August I'm guessing it is a bad earth somewhere?

Cheers, Chris

[Wedg1e]

From memory there isn't a local earth point at the rear of the car, it comes down from the front as a wire in the loom. Are all the connectors on/to the light units themselves free from corrosion? Those Fuego units are prone to the 'fingers' that link the bulbs to the 'circuit board' going cruddy which will result in the current to the lamps taking alternative routes.

[jmorgan]

They are a pain. I ended up hard wiring the things and solved all the "working one second, bust the next". Wasn't blowing any fuses though but then my reverse is not working.. Had a piccy somewhere but it was uploaded with photobucket and I have deleted my account. If I find the piccy I will pop it up.

[CHJ]

Thanks for replies.
Problems resolved after quite a bit of headscratching ... the dodgy brake lights when the fuse wasn't blown was caused by general corrosion under the clips on the pcb part of the light unit - all cleaned up now and working properly. The blowing fuse was caused by the live wire to the reverse switch having come adrift and was actually wedged against the gearbox casing causing a short-circuit when reverse was engaged. Just chopped the connector off for the time being as couldn't get to the switch properly, so no reverse lights at the moment but at least I know the brake lights do. Can't understand why they used the same fuse for reverse and brake lights, but there must have been good reason at the time.

Cheers, Chris

[GV]

I did away with renault connecting block and connected an earth to each of the neg terminals on each light socket along with the corresponding light connection. There's an earth connection that runs to the rear shock mount that feeds the rear lights.

If you decide to do the same thing you will need to remove the copper circuit board to avoid shorting out. The finished result will mean each light has its own connection easily tracebale if there's a problem.