Topic: Headlights on/gauges off?!?!?
in Forum: C3 Electrical
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Royse City, TX - USA
Joined: 11/16/2007
Posts: 62
Vette(s): 1978 L48, p/s, p/w/ factory ac car factory manual trans has a 350 crate engine w/260hp, but also have original which may be rebuilt- we also have a 76 w/ a 454, and 74 350 in various stages of being rebuilt, plus an 86 and an 02....
OK- so I'm learning what you all have been saying.... but it will all work soon. Car is home, but when I turn on the headlights- which work wonderfully by the way- 3/4 of the gauges stop working. I'm guessing its electrical- I dunno.... has anyone else had it happen? Any ideas? PLEASE!! Oh- and also- front turn signal doesn't work- back is fine, but right front won't do anything- not a bulb, not the switch or back wouldn't work- help...............
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Sounds like a ground issue. I had to add a ground wire to my gage cluster because when I turned on the headlights the gages would go nuts. The issue was the ground wire had been disconnected by the PO when he installed a after-market radio. I added a ground wire to the gage cluster and no more issues.
Brian - NCM Lifetime Member
73 coupe L48, Flat-top pistons, Performer RPM Heads, Crane Cam and roller rockers, Holley 650 vac sec. Performer intake,
3.55 gear BTO 200-4R trans,
Leather seats, Seatbelt Plus 3point seatbelts, Pioneer CD player
Magnaflow Exhuast System
Dewitt radiator and dual electric fans
Borgeson Steering box
I have an 81 wich I believe is the same wiring. I had a problem that when I turned the headlights on the gauge cluster would go out(not the speedo & tach). I found an open trace on the cicuit card from the plug to the temp gauge. Put in a jumper and fixed it. Check the fingers on the cicuit card to make sure they aren't touching. Let me know what u find cause info is priceless! shelly 81
Former Member
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Royse City, TX - USA
Joined: 11/16/2007
Posts: 62
Vette(s): 1978 L48, p/s, p/w/ factory ac car factory manual trans has a 350 crate engine w/260hp, but also have original which may be rebuilt- we also have a 76 w/ a 454, and 74 350 in various stages of being rebuilt, plus an 86 and an 02....
Thank you guys sooooooooo much!!! I will check out both options tommorrow in the daylight and get back to you- again- thank you!!
Lifetime MemberHOWELL, NJ - USA
Joined: 5/18/2004
Posts: 6812
Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
The printed circuits are notorious for separating. You can get them at best prices from Wilcox Corvette on ebay if that's what it turns out to be.
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Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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All of the above issues will be a connector, or loose ground.
The single turn sig not working, if you know the bulb is good, could also be a bad ground. The sockets can develop a condition known as being "ground-challenged", whereby the ground wire that goes into the socket can become unsoldered, or corroded. Try wiggling the wires on the socket with the signal on...
Does the park light work on that side? How about the hazzards for that side?
And...it can actually be the t-sig switch. The circuits are separated in the switch...this keeps the front t-sigs from glowing when the brakes are on.
I'd look for a bad ground at the socket, tho...that's the most common problem.
The single turn sig not working, if you know the bulb is good, could also be a bad ground. The sockets can develop a condition known as being "ground-challenged", whereby the ground wire that goes into the socket can become unsoldered, or corroded. Try wiggling the wires on the socket with the signal on...
Does the park light work on that side? How about the hazzards for that side?
And...it can actually be the t-sig switch. The circuits are separated in the switch...this keeps the front t-sigs from glowing when the brakes are on.
I'd look for a bad ground at the socket, tho...that's the most common problem.
Joel Adams
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Are you sure the bulb works? Did you swap front and rear or side to side to check?
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Former Member
Send PM
Royse City, TX - USA
Joined: 11/16/2007
Posts: 62
Vette(s): 1978 L48, p/s, p/w/ factory ac car factory manual trans has a 350 crate engine w/260hp, but also have original which may be rebuilt- we also have a 76 w/ a 454, and 74 350 in various stages of being rebuilt, plus an 86 and an 02....
its a loose ground. Hazzards work, switcehed bulbs, dash doesn't loose lights- just some gauges stop...... its gettin there.... THank you all sooooooo much for the help- I just want it all done already (-: and now... for the latest- my suspension seems to be getting really loose. YIPPEE. I love this car- but I think I'll love it even more when EVERYTHING WORKS.....for at least a few weeks...lol
in Forum: C3 Electrical
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