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Dash lights out!

Old 09-02-2014, 09:00 AM
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jbaron
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Default Dash lights out!

The fuse keeps blowing out on the dash lights! It was suggested it may be a ground problem. How do I trace this down? Wilcox?
Old 09-02-2014, 11:30 AM
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MelWff
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have you tried tracing the circuit to see what else other than the bulbs are in it? I didnt print the diagram below but it looks like the flasher may be part of it. Fuses blow when a hot wire touches ground when it shouldnt. A ground wire does not cause a fuse to blow.

http://www.keystonestatecorvetteclub...tte%201974.pdf
Old 09-02-2014, 06:53 PM
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DUB
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Dark green wire from the headlight switch supplies 12 volts to the 1/2 size fuse in your fuse panel. Then...this 12 volts goes into a gray wire that goes to all your gauge lights, radio and cigarette lighter light.

YOU CAN NOT pull the fuse and then check the terminal that goes to your dash lights and check for a ground BECAUSE it will show a ground...because you have ALL of your lights installed....thus it is 'finding a ground' through the filament in the bulb.

IF it were me...I would pull the side cover on the drivers side of your console by the radio and see if that gray wire is touching something...then I would check and see if the light assembly for your cigarette lighter has fallen out and the terminal is touching something metal.

To determine which side of the fuse terminals is getting power form the headlight switch and which one is going to your light bulbs...unless you can read the diagram. PULL the fuse. Then using a test light or volt meter....pull the headlight switch and touch the test light or volt meter to the terminals one at a time. The one that goes to 12 volts is the one from the headlight switch....thus...the other one is the one going to your light bulbs.

DUB
Old 09-02-2014, 09:12 PM
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jbaron
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Thanks DUB, I'll check it out!
Old 09-03-2014, 07:17 PM
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John A F
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I had this problem with my 79. It turned out one of the copper pathways on the flex printed circuit board behind the speedo/ tach came loose and would occasionally ground out. Replacing the circuit board solved the problem. It even made the parking brake warning light operational, which never worked since I bought the car 5 years ago.
Old 09-03-2014, 07:21 PM
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DUB
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Originally Posted by John A F
I had this problem with my 79. It turned out one of the copper pathways on the flex printed circuit board behind the speedo/ tach came loose and would occasionally ground out. Replacing the circuit board solved the problem. It even made the parking brake warning light operational, which never worked since I bought the car 5 years ago.
Glad that you got your repaired and working...but...a 1974 is completely different so the printed circuit board was not used in this year model.

DUB
Old 09-03-2014, 08:13 PM
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69Vett
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the steering column support is a cast item, and almost all off them have very sharp edges, easy to cut into wire harness, check for cut wires in this area.
Old 09-04-2014, 11:47 PM
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jbaron
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Thanks DUB, it was the gray wire in the console that was grounding out.
Old 09-05-2014, 06:49 PM
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DUB
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Originally Posted by jbaron
Thanks DUB, it was the gray wire in the console that was grounding out.
WINNER...WINNER...CHICKEN DINNER!!!:

Heck...even a broke clock tells time correctly twice a day.

I figured mentioning the obvious first...or at least what I have encountered the most.

DUB

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