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Strange Electrical


Hello, on my 1967 Convertible.  When the car is NOT RUNNING, all lights work great.  When the car is running..  The break lights cut out after about 5 seconds and never come on again until the car is shut off and re-started.  Headlights start to flash after a few minutes.  Everything is great and operates as it should with the engine off. 

Do I have a bad alternator, or is the electrical going to the lights wired wrong, etc???  Any ideas?  Thank You..

Interesting.  The power for the lights you're having issues with all come out of the headlight switch, which has a circuit breaker built in.  When it starts going bad it can trip and cause the blinking headlight issue (when the car is running there's more current available to light the lights so it could still be a bad breaker).  I did not know that the brake lights were wired through the breaker though.

It's possible that you have a bad diode in your alternator so I think I would get that and your regulator checked (most auto parts stores can do that for free).

If those check out, I suggest replacing the headlight switch.

I'll check that..   Thanks for the advice..

So. When the car is cold all the lights work properly.  After idling until it warms up is when it starts freaking out. Blinking and so forth.  When I shut the engine off the lights continue to blink.   It also does this when the car is off.  When all the lights are on (and car is not running and is cold) it's fine, then after about 10 minutes, they blink.  If I pull one light off, it all returns to normal..

So what part of the electrical works with the head and tail lights that is sensitive to heat from voltage....

Seems fixed.  As simple as a new light switch and break light trigger switch...  So far so good...


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