Escort Estate rear lights

[iwbus]

I have a 1993 Escort estate and the left hand light cluster works fine but the right hand side tail light has stopped working. The other lights in the cluster work fine, the brake light (on the same bulb) works fine plus if I put the bulb in at 180 degrees to the way it normally goes in then the tail light works fine. I can't keep it in the 180 deg position though because of the position of the bayonet holdings. Anybody know what's wrong with it???! What should I be checking? The front lights work so I think I've ruled out fuses as the cause of the problem

[RAYMAN]

i dont know if this is your problem but its a long shot, check the return of the neg return to the battery,my wifes back lights had a corroded contacts on the plug to the printed cct board i over came this by fitting a length of wire using a self tapping screws one end on the cct board neg return cct and the other to the body of the car

recheck wether im correct im talking about which ever is the return through the body neg - or pos+

[Ewood27]

When you put the bulb in 180 deg out, are you sure it's the tail light filament that lights?  Or is it the brighter brake light filament?  This sounds to me like a simple case of a twin-filament bulb where the lower-rated filament has failed.  New bulb.

[iwbus]

Got it sorted folks, thanks for your help. 2 problems in evidence, the first being a single filament bulb where a double should've been, the second was a blown fuse. I know a fuse is a simple thing to check but I had assumed that the front and rear side lights would be covered by the same fuse and the front lights were still working. Always the simple things eh?