["QUICK-SILVER"]

Originally Posted by Frank69

Would a new sending unit provide a proper ground? Thanks, Frank69

May be nothing wrong with the one you've got. It only grounds to turn the light on after the engine over heats. Don't know what temperature that is.

You'ld hope the light would come on before steam starts coming out from under the hood......but that's not usually how it works.

Haven't tried it, but you could probably test one of the sending units for lights with a small kitchen torch, your multi meter and an infared thermometer.

Need to try looking that up. Exactly what temp do those units go to ground.

FWIW that's why I like gauges
Clay

[Frank69]

Wonder what provides the ground for the test when the ign switch is in the accessory mode? Now Lite is not lit until key is moved to start mode, lites until motor fires then goes to off with the other idiot lites. One of the things I would change if I were ordering this car new is the gauge package. If I recall correctly all three lites lit when the ign was moved from Off to Accessory mode. Now only two lite in that mode but we know the Temp bulb, socket, pc board and the green wire are doing their job. Car has never had a heat prob so for now so I will drive it like this. The other lites are all working fine including the Emergency Brake Warn Lite. Thank you for all your expert advice and patience.
Frank69

["QUICK-SILVER"]

There's a ground circuit built in the ignition switch that's for temp bulb test while cranking. Only other time the temp bulb comes on is if the engine over heats.

So all is good and working like it's suppose to. You just thought all three lit up in acc. Other than e-brake, alt and oil should be your only lights with key on and engine off.

Clay

[Frank69]

Clay, thanks for your answer and I will be forever grateful for your kind assistance. This completes this project for me. Very Best Regards, Frank Woodard Tulsa, Okla