Ford Escort stop/tail light problem

I have a 1994 Ford Escort wagon. If I turn on the lights, the rear tail lights are on just fine, but when I step on the brake, the 3rd light and right stop light go on, but the left stop/tail light goes out. I
have replaced the bulb, but there has been no change in what happens.
Am I looking at a short circuit, a defective stoplight switch, or something else?
Any help would be appreciated.
-----------Howard
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not understood... if you step on brake, without tail light on, does the left one light at all.. even dimly?
Sounds very much like a poor ground for that left socket, trace wires to it.
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you pay..DEAL with it!
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yep, bad earth
m
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If I do NOT have my lights turned on, both stop lites and the 3rd lite are just fine. It's only when I have my lights turned on which means that the tail lite is on until I step on the brake and then the lite goes out.
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hiya,
yeah. 'cos the power will take a route down the side light wires, but when you switch them on they're fighting against the 12 volts from the side lights so they cancel each other out and then find another way to earth. check the -ve earth point/connections, honest, you're looking for a more serious problem than you've got.
m
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Please define what you mean by serious problem.
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Pull out the left socket with bulb in it, have someone step on brake... see if BOTH filaments of the bulb dont light... then turn on taillights and do same..
The tail filament will go OUT when brake light is engaged because it has no path to ground/earth.... Common problem!
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