82 temp gauge question
Thread Starter
2nd Gear
Joined: Jul 2013
Posts: 2
Likes: 0
82 temp gauge question
On my 82 Corvette the engine water temp gauge works correctly... until I turn on my lights. I have narrowed it down to the fact that when I turn on even my parking lights, I can run the temp gauge up and down by turning the dash lighting rheostat up and down. As I turn the dash brightness up, the temp gauge rises, then it lowers as I turn down the brightness. No delay, it runs up and down as if you were operating radio volume. It seems directly proportional. Just wondered where to start looking. The light in the temp gauge seems to be not working so I don't know if that's related or if it's a ground problem or what. Also my torx tools didn't seem to want to fit the cluster screws. What size tool does that take? Just didn't want to strip out the heads. Appreciate any help. Thanks
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Sounds like a bad circuit board (the flexible circuit piece) behind the gauges. That is the only thing that i know of that could tie the rheostat for the lights to the temp gauge other than some really ingenious Bubba rewiring.
Racer
Joined: Sep 2009
Posts: 437
Likes: 3
From: Alvin Texas
You have a open ground problem in the gauge area, the light circuit is robbing the -. The screws in the front of the panel are fake, don't try to turn them. To access the gauges and wiring you must remove the center gauge cluster. Do a search in this forum for the process of removing that cluster.
Oh welcome to the Forum.
You need to get the Factory service manual and an assembly manual, available from several Forum sponsors.
Oh welcome to the Forum.
You need to get the Factory service manual and an assembly manual, available from several Forum sponsors.
Last edited by bpassmore; Jul 4, 2013 at 05:19 PM. Reason: addition
Thread Starter
2nd Gear
Joined: Jul 2013
Posts: 2
Likes: 0
You have a open ground problem in the gauge area, the light circuit is robbing the -. The screws in the front of the panel are fake, don't try to turn them. To access the gauges and wiring you must remove the center gauge cluster. Do a search in this forum for the process of removing that cluster.
Oh welcome to the Forum.
You need to get the Factory service manual and an assembly manual, available from several Forum sponsors.
Oh welcome to the Forum.
You need to get the Factory service manual and an assembly manual, available from several Forum sponsors.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
If this is only one gauge doing this then I would have to take a hard look at the PCB behind the cluster....
When a ground is missing from the #1 body mount or if the A pillar ground is broken.. The lamp switch will chase a ground and mess with all the center dash gauges except the clock.
But since the issue seems to be just one gauge I think I would pull the cluster and take a look. One of the fingers on the board may be touching another on on the pcb. I'd take a hard look at it right above the center connector where the power wire is for the lamps and the ground is for the lamp and the temp gauge. If you look at the picture below, the ground for the lamp is the same
When a ground is missing from the #1 body mount or if the A pillar ground is broken.. The lamp switch will chase a ground and mess with all the center dash gauges except the clock.
But since the issue seems to be just one gauge I think I would pull the cluster and take a look. One of the fingers on the board may be touching another on on the pcb. I'd take a hard look at it right above the center connector where the power wire is for the lamps and the ground is for the lamp and the temp gauge. If you look at the picture below, the ground for the lamp is the same
Last edited by Willcox Corvette; Jul 5, 2013 at 11:23 PM.
