Topic: Dash light problem
in Forum: C4 Electrical
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Raptor003
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decatur, AL - USA
Joined: 4/3/2014
Posts: 8
Vette(s): 1st and only Vette so far. 1994 Polo Green Matallic base coupe. Bought in November 2013 with 200,000 miles on odometer. Runs great and almost everything works.
My 94 base with electronic dash works fine until I turn on the headlights. None of the dash lights come on and the LCD display goes blank.
|UPDATED|3/7/2018 1:24:32 PM (AZT)|/UPDATED|
Turn the lights off and they reappear.
A friend told me he thinks heard there is a relay under the dash that operates the system for night driving but I have no idea if that's true or not.
Has anyone else had this problem? If so, I would sure like to know the solution, tired of daylight driving only.
|UPDATED|3/7/2018 1:24:32 PM (AZT)|/UPDATED|
Adams' Apple
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Duncanville, TX - USA
Joined: 3/18/2009
Posts: 2246
Vette(s): 1985 Coupe-L98/Auto,Bright Red/Carmine.
1974 Coupe-L48/4speed, Medium Red Metallic/Black Deluxe.
Have you tried turning the headlight knob....just to see if it is turned all the way off? I think clockwise is off, and c-clockwise is on...but it may be just the reverse. Sounds simple, but lots of folks forget.
Other than that, it's possible the headlight switch is to blame. Not aware of any relay that controls the LCD/gauge lighting, but there is a fuse...might check the fuses out too.
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Kettsvette
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Scottsdale, AZ - USA
Joined: 7/8/2014
Posts: 31
Vette(s): 1988 Dark Red Metallic Convertible with sports seats, Delco/Bose radio system, Z52 suspension
My '88 didn't have a relay for these lights but they are operated from the light switch then thru a fuse. It sounds like the switch might be an area to check but before you go through the process of taking it out and testing it, I would try to see if using a "TV Tuner" cleaner spray might help with the problem. I have found that electrical connections on the older cars may get some corrosion on the contacts which could cause a problem but using this spray seems to clean them up without pulling the car apart to get to a switch. Once you spray around and inside the switch stem rotate the stem back and forth so get the spray to work on the contacts. If this does not work then you may have to spring for a new lights switch.
Raptor003
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decatur, AL - USA
Joined: 4/3/2014
Posts: 8
Vette(s): 1st and only Vette so far. 1994 Polo Green Matallic base coupe. Bought in November 2013 with 200,000 miles on odometer. Runs great and almost everything works.
It's not a fuse, all are OK. The dash light rheostat seems to feel intact so I was searching for something else.
A guy who comes in the O'Reilly's I work for has 2 C4's and said that a relay under the dash should be the problem so that's why I was looking to find out some more about it.
Thanks for the idea's, I am open to all possibilities.
Love the C4's and want mine back on road soon.
It could be the instrument panel itself. Broken solder, weak power supply unit, etc. There are several companies that are experts repairing these. You could contact one and describe your symptoms. They could tell you what test you could run. It's not hard to remove if required. Best of luck.
Raptor003
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decatur, AL - USA
Joined: 4/3/2014
Posts: 8
Vette(s): 1st and only Vette so far. 1994 Polo Green Matallic base coupe. Bought in November 2013 with 200,000 miles on odometer. Runs great and almost everything works.
thanks for the reply, I've been so busy at work I haven't had time to even look at my Vette in about a month.
I will contact some of these people, maybe they can give me the right insight.
Great to have multiple minds working on my problem.