Topic: Tailight gremlin

[ahamasnoj]

Help Please.  1966 coupe. My left taillight will not come on when I apply the brakes. The right side does though. The blinker light works as well as taillights when the headlights are on. Only the left brake light doesn't come on. I have replaced the taillight housing, extension wires and the complete rear wiring harness that runs from the taillight up the left hand side of the car and under the dash. I replaced the brake light switch on the brake peddle yesterday and still it doesn't work. I switched bulbs also. What can it be?

ahamasnoj

[ruppstang]

Turn signal switch.

[midlife]

Turn signal switch.

Agree that that is probably the #1 cause.  Other potential causes are:
(1) busted filament in the bulb
(2) bad contacts in the bulb housing
(3) incomplete connection at the connector for the tail harness to main harness
(4) pinched or broken wire in tail-light harness.

[suskeenwiske]

Just for grins, switch the left and right Tail Light Bulbs. If there's no change, then at least you know that the Bulb is OK, but if the problem moves to the right, then check to be sure you have the correct Double Filament, (1157), Bulb and/or try a new Bulb.

Other than that, there are any number of areas that could be the cause as already mentioned by previous responses; a good digital volt meter may become your best friend to help with this issue.

All the best.

Ray