Faulty Wiring - Peugeot Van!

[tec67]

After replacing a bulb for a rear brake light (for Peugeot Partner Van) I have a problem that when I brake the side lights (front & rear) come on, as well as the brake lights.
Also when the side lights are switched on the brake lights will not work at all.
I have changed the bulb and also removed it completely but problem is still there.
I suspect maybe a short circuit somewhere, but exactly where I don't know.

Any ideas please

Any help would be much appreciated. Thanks.

 

[sparkyfrog]

Hi
I don't think the lighting is part of the multiplex wiring so:
The things that come to mind are
1) A poor earth somewhere around the lamp unit - the usual problem with weird lighting faults.
2) Corrosion in the lamp base
3) A wire disloged as the lamp unit was moved.
I have a virtually identical Berlingo Multispace but I've not had the light unit off yet.
Unfortunately Mr Haynes doesn't do a manual - not enough vehicles around apparently. Funny how many I see round our way.