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Old 12-19-2024, 10:14 PM   #1
pontiacvince
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Electrical

Still having electrical issues with my '71. My dash lights weren't working as well as brake lights. I replaced the headlight switch and that fixed the dash light problem....for a few minutes. Don't work again. Replaced the turn signal switch and the brake lights work. Not sure what to do about dash lights. Any suggestions???
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Old 12-19-2024, 10:23 PM   #2
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Lightbulb Re: Electrical

Check all grounds, and make sure the fuse isn't blown. The instrument lamps circuit are run through a rheostat in the headlight switch. It is possible it is defective.
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Old 12-20-2024, 04:20 PM   #3
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Re: Electrical

Do the lights in the heater panel light? If not then it's likely a problem in the 12v positive power supply to the lights instead of all of the grounds being bad. Do what 1970cstblazer said and check the fuse and the switch.
I recently had the brake lights quit working on the Burban. The fuse looked good but a test light showed it wasn't making a good connection in the holder. I removed the fuse, tested it and found it was good and the caps were tight so I reinstalled the fuse I had brake lights again.

Good luck and let us know what you found.
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Old 12-20-2024, 09:45 PM   #4
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Re: Electrical

The dash lights' power originates with the tail lights. If the tail light fuse blows, the dash lights will also fail.. Check the tail light fuse.
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Old 12-24-2024, 05:38 PM   #5
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Re: Electrical

I'm thrown off by the dash lights working for a very short time after installing a new headlight switch. I've checked and rechecked all the plug connections and still no dash lights. I visually checked all the fuses and they looked Guess I'll pull out the multimeter and check continuity....
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Old 12-24-2024, 06:23 PM   #6
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Re: Electrical

Quote:
Originally Posted by pontiacvince View Post
I'm thrown off by the dash lights working for a very short time after installing a new headlight switch. I've checked and rechecked all the plug connections and still no dash lights. I visually checked all the fuses and they looked Guess I'll pull out the multimeter and check continuity....

Does the dome light work if you rotate the headlight switch knob to the on position?
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Old 12-25-2024, 08:13 PM   #7
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Re: Electrical

This photo may help. (Thanks to Palf70Step for the photo! ). I've had problems in the past with the wiper on the dimmer portion of the switch not making good contact with the coils on the rheostat. (Green circle) Check that the rivet that holds the terminal just above the green circle is tight and it makes conductivity with the terminal and the wiper.

Broken parts on the shaft in the area in the yellow circle can cause the rheostat to lose contact with the wiper.
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Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help.
RIP Bob Parks.
1967 Burban (the WMB),1988 S10 Blazer (the Stink10 II),1969 GTO (the Goat), 1970 Javelin, 1952 F2 Ford OHC six 4X4, 29 Model A, 72 Firebird (the DBP Bird). 85 Alfa Romeo
If it breaks I didn't want it in the first place
The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377
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Old 12-25-2024, 08:59 PM   #8
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Re: Electrical

pontiacvince

Does your wiring harness still have this ground clip?

Is the clip and surface clean?

Name:  ground clip.jpg
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Old 12-27-2024, 04:24 PM   #9
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Re: Electrical

Quote:
Originally Posted by LockDoc View Post
Does the dome light work if you rotate the headlight switch knob to the on position?
Doc, yes, everything works except the dash lights. I don't drive it much at night, but would still like it to work as it should.
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