Rear lights problem

[thegazza]

Hi
ok will try and explain this the best i can it a 57 plate transit
both main rear lights work fine,but my number plate lights and rear top door stop light dont well they do but not as they should.
one plate light is on but not very bright and the other is just visiable but also the top door stop light is on aswell with just side lights switched but only just.
if i pull a plate light out the other bulb gets brighter and vice versa. if i put my foot on the brake pedal the main light clusters work as they should but i loose both plate lights and door stop light!
sounded light a bad earth to me,to which i have had the rear passenger cluster out and cleaned and redone the earths to the body behind it also cleaned the number plate lights and connections.
is there anything im missing or am i trouble shooting the wrong idea.
Thanks in advance for any advice

[ake]

Test the Earth continuity through the wiring loom from the Earth point behind the tail light to the lights in the door

The loom is known to break and fail between van and door

[thegazza]

Test the Earth continuity through the wiring loom from the Earth point behind the tail light to the lights in the door

The loom is known to break and fail between van and door

Hi bang on with that m8 earth had snapped in two in the rear door loom
http://tinypic.com/view.php?pic=ru8dis&s=9#.WXUDEITyuUk
all repair and working