Brake lights not working. Need help, please.

[grandaddy]

I am not a new member but have new log in. My car is a 69 GTX. Problem is the brake lights do not work now, they were intermittent but now nothing. ALL other lights work fine. I viewed the FSM brake light diagram and it looks like one of two probable areas. 1) Brake light switch on brake pedal or 2) turn signal switch in steering column. I by passed the brake wire switch with a jumper cable. With it jumpered, brake lights worked once, next time did not. I have two new switches, so I removed the switch. Just in case, why not?? I have a minimum knowledge of electrical systems, so I would appreciate any suggestions on how to isolate or identify where the problem is.

 

[Beekeeper]

check the grounds for the tail/brake circuit. By your description it sounds like that's the problem.

 

[dvw]

check the grounds for the tail/brake circuit. By your description it sounds like that's the problem.

The stop lamp circuit feeds the turn signal switch. If the turn signals work the harness from the switch back (including the ground) are good. If jumping the stop lamp switch doesn't light the stop lamps the turn signal switch is internally open from the stop lamp feed to the tail lamp feeds.
Doug

 

[RT K_line]

X2 on the turn signal switch. If you take it apart you will probably find the plastic melted on the switch somewhere around the pins. Good luck.

 

[kiwigtx]

X2 on the turn signal switch. If you take it apart you will probably find the plastic melted on the switch somewhere around the pins. Good luck.

Agree about this (it happened to me in a '70 GTX)

BUT

Check the easy stuff first - grounds at the trunk end.