Topic: Gauge Gremlins
in Forum: C3 Electrical
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Thanks to all the great help I received from you guys I was able to accomplish my major winter project and now have terrific brakes.
The other small winter project is dragging into another year. That is trying to get my gauges working correctly.
I replaced the clock innards and that is taken care of, but the water temp gauge I replaced is still not working. Additionally, the fuel gauge has now decided not to work either.
I have checked and re-checked all electrical connections and have replaced the water temp sender.
I get what appear to be correct readings from both senders. (variable resistance depending on temperature and fuel level)
Any ideas?????
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you might check the plug that plugs into the printed circuit board of the instrument cluster the little copper contacts might move. if you have the diagram check the resistance of your sender from that connector, I beleive the temp sender is dark green. then you would now if it is in the wiring or in the instrument cluster
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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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Check for good grounds on the gauges, too.
Where are you testing the sensor readings? At the sensor, or at the gauge/panel connector?
Since you've had the gauge cluster out(more than once, I presume), I'd lean towards a bad connection there, prolly on a ground circuit.
Also, make sure the fuse is good for the gauges, as the temp and fuel gauge use the same fuse.
Do you have a wiring diagram?
Where are you testing the sensor readings? At the sensor, or at the gauge/panel connector?
Since you've had the gauge cluster out(more than once, I presume), I'd lean towards a bad connection there, prolly on a ground circuit.
Also, make sure the fuse is good for the gauges, as the temp and fuel gauge use the same fuse.
Do you have a wiring diagram?
Joel Adams
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Also, I have the EZ Wiring Diagrams and they are great.
Found the fuse to be okay.
I checked the wiring diagrams and the gauge grounds are common with the radio (which works) and the parking brake indicator light (which also works).
Looks like the center gauge panel wil have to come off again. (for the umpteenth time)
Thanks,
Before you pull the gauge cluster, with the key on disconnect the sending unit wire to the temp sending unit and look at the gauge reading. Then ground the wire and look at the gauge again. One way, it shoud read max, the other way it should read cold. You can do the same with the fuel gauge. If they don't respond, pull the gauge cluster. If they do, the problem is not the gauges. Be sure to check the wiring from the gauge to the sending unit as well.kstyer 2008-08-17 16:44:08
GOT THE GAUGES WORKING!!!!!
The water temp gauge has one of the four posts without a connection that is supposed to have an insulator on it. I had an insulated washer that wasn't totally insulated. I replaced it and both the water temp and gas gauges started working.
Talk about gremlins.
Thanks for everyones help.
Hey guys/gals, I have a related question...where IS the temp sender on a '79 L-48 motor? Mine stopped working all of a sudden. My oil pressure never worked since I've had the car but I figure it's the sender.
ku2002 2008-08-29 08:48:49
Thanks!
in Forum: C3 Electrical
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