My wife and I (OK, it's hers!) have a 1968 Dart 270
Slant 6, automatic transmission.

We have an electrical problem, summarized as follows:

1) Left and right blinkers work fine, front and back
2) Headlights work fine at the front
3) Neither taillights nor brakelights work at the back

We changed a fuse for the tail/brakelights, but this results
in the back lights being permanently lit, even with no key
in the ignition.

4) Also, the hazard blinkers don't work correctly: again,
everything's fine at the front. At the back, if the hazard
switch is on (up), nothing happens, UNLESS the indicator
steering control is up or down, in which case both lights
blink correctly at the back!

Looking at the lightbulbs at the back, only one of the two
filaments is ever lit - either when blinking or when in
permanently-on mode.

I read somewhere that the problem might be due to the
"brake light switch" being in the wrong position. Where is
this switch located? Also, does this sound like the solution
to our problems?!

Thanks in advance.

Chris Gittings

You have the classic symptoms of a bad ground. It could be anywhere, but first check your tail light housings and engine to chassis straps. That's where I've found the most problems.

The brake light switch is a little switch that is mounted under the dash and it actuated by the brake pedal. It is a little plastic unit with a plunger hat contacts the arm which the brake pedal is mounted on. This unit can be pushed out of its proper positon over the years and end up leaving the brake lights on all the time. Check that first. Then start looking at grounds. I would focus first on the grounds for the tailight housing. Make sure that the surface where the screw passes through the housing and into the fender is clean and rust free. Wet or damp sockets will also malfunction.
If those are in good shape I would double check and make sure you have the proper bulbs in the housings. I have seen many cars whose brake lights malfunctioned simply because someone had put a single filament bulb where a double should have been and vice versa. While you are at it make sure your front turn signals have the proper yellow bulbs, not the clear ones that everyone seems to replace them with.

Reed

Seems crazy, but I discovered you can install a brake switch incorrectly, pulled switch from 66 doner to install in the 63, when installed as per 66 standards produced the condition you discribed, When I reversed the mounting bracket and swich problem went away. All these years I thought there were no differences from 63 to 66 switches and brackets.

I'm delighted to say that our problem turned out to be relatively
easy to fix: once we had located the brake light switch, it was
clear that it was not being actuated by the brake pedal, and was
permanently 'out' and thus the lights were on.

It was a great moment the first time I pressed the button
manually, and my wife confirmed that the lights had gone out!

With a little effort, we were able to realign the button so that
it was correctly pressed in when the brake is at rest, then
released when the brake is pressed.

Now, we have working brakelights and taillights...

Thanks again to all (especially Reed) for helping to get us
back on the road!

Chris G