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Topic: electrical gemlin somewhere (Read 839 times) previous topic - next topic

electrical gemlin somewhere

just started today.  All will be fine, until i turn the headlights on, then things go nuts, the gauges go crazy, the wipers will barely move and the electronic controls and clock go out. The highbeam and 4 way indicators light up as well.  It happens when I turn the heater on as well.  I think it's the lightswitch but i dont have a spare.  can you repair those things or not?  would it be the electronic climate control?  I checked the alternator and it's putting out 13.5V.

electrical gemlin somewhere

Reply #1
Bad ground somewhere?
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electrical gemlin somewhere

Reply #3
ignition switch, hmm didnt think of that cuz it's new, but i have a spare.

electrical gemlin somewhere

Reply #4
Did you happen to inspect the wiring at the ignition switch harness when you replaced the switch? The wiring can melt the harness end, wires can fall out, etc. We've seen it happen before.

Otherwise...if the problem happened with JUST the headlight switch then you'd be on the right track. But with the heater on also...something's pulling a hell of a load somewhere.

Have you blown any fuses or tripped any circuit breakers, to your knowledge?

electrical gemlin somewhere

Reply #5
the original ignition switch pigtail was burnt so i bought a new one and repinned it. It's been fine for 6 month at least.  Now, the more accessories i turn on the worse the draw is BUT, the alternator puts out a continuos 13.5 V.  The head light switch is an instant draw when i turn it on and gets worse from the parking light detent to full headlights on.  Even the dimmer jacks everything up.  The electronic heater control does the same thing, only intermittently.  When I turn the headlights on it affects EVERYTHING...the wipers barely move, the gauges go crazy, especially the speedometer and the 4 ways and highbeam indicators light up. I'll swap out a spare ignition switch this weekend.  Are the headlight switches fixable? I hear they have some sort of resistor in them.

electrical gemlin somewhere

Reply #6
I believe I still have a extra h/l switch here if you need one if you cant find one closer.

electrical gemlin somewhere

Reply #7
Don't Turbo Coupe's have external voltage regulators? That's what I'd suspect then. What is the voltage at the battery at idle, under draw (lights on, heater on, wipers on, radio on, etc.)? You have to be dipping well under 12v in that case. Even a good voltage regulator will flirt with 12v under that cirspoogestance. Voltage regulators have a way of passing tests while degrading.

There is a circuit breaker that's built into the headlight switch. It's non-replaceable; have to swap out the switch. That's why I asked if you heard it tripping...your lights would be flashing on and off if it was.
Reference here: http://www.coolcats.net/tech/reference/fuses.html

electrical gemlin somewhere

Reply #8
I think Cougarman's on the right track: A bad ground. More specifically, a bad body ground (a bad engine ground would cause a no-start). Put a jumper cable on your battery's ground post and the other end on the body of the car where you can get a good ground (maybe strut mount nuts, or if the cable's long enough, the door latch striker) and see if the problem goes away. If you've got a double cable with black and red clamps use only the black clamps on each end.

Ignitions switch problems shouldn't affect headlights. It usually affects heater fan, cluster and turn signals (that seems to be the circuit that fails most often). The headlights are not switched through the ignition.
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electrical gemlin somewhere

Reply #9
i'll try that this weekend. the exterior lights themselves are Ok, it's everything inside the car going nuts.