64 Brake light problem

[Ed S.]

Issue pertains to a 1964 convertible, L76, 4 speed manual w/power brakes, and with back-up lights. I noticed this morning that with engine idling, both rear tail lights intermittently would come on for a few seconds (or less) and go off - as if a wire was loose and making enough contact to complete the circuit and delivering juice to the bulbs. No other lights were on or demonstrating a problem.

I drove home, parked in the garage, turned everything off. Checked the rear lights - they were off. Checked them 15 minutes later and the brake lights were on - bright - and the lens were warm (not hot) to the touch. I pulled the brake pedal up with my hand - it had no more than 1/4 travel - lights went out. Let the pedal sit and in less than a minute lights came back on. I lifted the pedal again - lights off. Just taping the pedal with my finger will turn the lights on. By the way, there has been no recent work on the brakes or electrical system and the brakes work fine, solid pedal, no mushy feel to it.

I suspect that it is the brake light switch that is going or has gone bad. But..... should there be any travel in the pedal at all? Could the brake pedal return spring be the problem and not the switch? Both parts are not expensive - should I replace both? Is there something else that might be causing the brake lights to come on?

[Bob R.]

Re: 64 Brake light problem

There is some adjustment in the switch try that first or it may need replacement.

[Dan H.]

Re: 64 Brake light problem

Ed, you might try adjusting the switch towards or away from the pedal a little. Sit in the car and watch the amp meter to see when the lights go on and off. Don't believe power brake cars had a return spring, booster serves that purpose. Have fun under the dash!
Dan

[Paul Y.]

Re: 64 Brake light problem

There is some adjustment in the switch try that first or it may need replacement.

Ed, very easy to adjust. Try a half inch open end (or 9/16) to loosen and then turn the pressed tin nuts by hand. Take the pressure of the switch by holding the pedal away from the switch and adjust a bit and see how it goes. When you like it , snug it back up again with the right wrench and you are done. Unless the switch is bad. Then just replace it. Get it close by counting the threads when you remove it.

[Ed S.]

Re: 64 Brake light problem

Paul,
Thanks - problem solved, it was just a switch adjustment. But I have to say, it was no easy task. Getting this 69 year old body into the necessary contortions under the dash to see and then adjust the nuts was no easy task. And then there were the very tight quarters up under the dash to operate in, i.e., getting a small wrench in there to loosen and then tighten the tin nuts. But is is working properly now. Brake lights come on and off when they are supposed to.

What concerns me is why the switch went out of tolerance in the first place, the nuts were tight and nothing under there or associated with the switch is moveable except the brake pedal and it returns to the correct stop position. Will have to monitor this for a yet to be identified problem. And yes, it is a good life. Thanks again to all.

[Leif A.]

Re: 64 Brake light problem

Ed,

The switch probably isn't what changed but rather the brake pedal arm. They "wear" over time...get a tiny bit sloppy and as you found out, that's all it takes for the arm to then contact and depress your brake switch. Be thankful for the adjustment built into the switch.