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i posted this a day or so ago
"my headlights in my (70 mach) after a short while will blink on and off... i put in a new switch in and still no dice... :0( all the other lights work fine including the sport lights in the grill..... there is a larger wire (black with and orange stripe) that goes into the headlight switch that gets pretty hot....... the lights will stay on longer if i only have the low beam on...,,, does the head light swicth have a ground that i've missed?..... any one have any idea what i can check?......i'm hoping to have her back on the road early next week..... thanks jace"

i got a few replies to replace the dimmer switch and i did... the lights stay on a little longer but still blinking . does the dimmer switch ground to the floor of the car? my car has had floors put in and the bolt holding the dimmer switch are a little loose..... could i try a little larger bolts?...... the black and orange wire is still getting hot........ also i have to take the battery cable off at night or when then the car set awhile or my battery will go dead.. so i know i have a short somewhere... think the problem is connected to each other?....... thanks for anyhelp on this jace
 

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Midlife will likely give you better advice but I'd start with an ammeter connected in series at the positive battery post to the cable, with all systems off, measuring any leakage....then work my way through the connections (wiring diagram would be helpful), isolating and eliminating each system (since you've noted troubles with the headlights...that would be first) until I found the source of the leakage. I would think, if it were a dead short, you'd be melting wiring or blowing fuses...

Electrical problems suck *G*
 
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I had the same problem, and the same frustrations when nothing I tried worked.

It took me weeks to nail down the cause, and then it happened by accident.

It was the pigtail that plugs into the dimmer switch, not the switch itself. So, whenever I tested the dimmer switch or removed it, cleaned it, and tested it with a continuity meter, it always passed the test.

I replaced the headlight switch and the pigtails that plug into the headlamps at the front of the car; I spent more than one weekend testing wiring with a meter.

Nothing worked.

It was only by accident while running back and forth from the front of the car, where I was testing the wiring with a meter, and the driver's seat to switch from high to low beams, that I noticed the lamps flicker briefly when I hit the dimmer switch. When I tried it again, no flicker. So it was intermittent---not a clean break, the wiring appeared to separate or short only sometimes.

That discovery led me to to the pigtail at the switch and that finally solved my problem.

Your problem may not be the same as mine, your wiring may be shorting out or breaking connection somewhere else.

But the point is, don't give up. (And don't plan on paying to get it fixed, unless you're prepared to pay for many hours of troubleshooting at shop rates).

You have to examine every little stretch of wiring and look for the unexpected (my problem was inside a molded rubber mass, no way I could inspect that; I just had to jiggle it the wrong way while the lights were on).
 

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You can fix it permanently by installing the headlight relay setup from Painless. It is not the "correct" way to fix it, but it will eliminate virtually all of the amperage running through both the headlight switch and the dimmer switch, which will stop the overheating and tripping.

I used this method on my '66 and am quite happy with it.
 

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Headlight switches have a built in circuit breaker... They will flash on and off when overloaded... Change to Halogen or H4 elements?

Don't go back to the standard lights, as Kent suggested, get a hedlamp relay....Mine came from NAPA.... #HR303 if I recall correctly.
 

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The problem isn't always in the switch. You could have a bad parking light that is grounding. Turn on the lights, and unplug them and see if the blink goes away...
 

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You might need to check+clean every ground you can find. Specifically the ones on the radiator support and driver's inner fender. If the main wire is getting hot, it means you have high resistance in the circuit somewhere. There are other causes, but corroded or disconnected grounds are VERY common.
 

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you are tripping your headlight circuit breaker with excess curent caused either by short to ground or using higher power lights than designed lights. you can hear ckt brdr clicking if you get close to your light switch and have quite ambient - got to stop that for proper ooperation. PM me if you want troubleshooting recommendations.
 
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