66 polara, put light on, engine temp rises!

[ian taylor]

yup she's throwing up a new one....drives lovely, temps all normal, put headlights on and temp guage (factory one) rises...lights off, down she goes....any ideas folks?

 

[traintech55]

Wow, this is a good one. Well the temp. gauge works by a voltage limiter sending power to the gauge to the sending unit which varies the ground. The only place these two circuits have anything in common is the Instrument panel circuit board. I would start with that and look to see if you have any broken or bent pins on the board at the connector. Also look at the board to make sure nothing could be letting power jump from one side to the other.

 

[mr. fix it]

check the grounding on the dash... it is likely feeding back through the gauges when you flip the lights on...

 

[ian taylor]

check the grounding on the dash... it is likely feeding back through the gauges when you flip the lights on...

that will be the next port of call...clock isnt working so was all due to come out anyway, also even on max, clocks barely light up....thanks for the help

 

[fury fan]

check the grounding on the dash... it is likely feeding back through the gauges when you flip the lights on...

Agreed. When an item doesn't receive positive voltage, it works poorly, if at all. When a ground is weak and it finds another one, funny things happen.

 

[LocuMob]

T

that will be the next port of call...clock isnt working so was all due to come out anyway, also even on max, clocks barely light up....thanks for the help

He only gauges I've had working on my car are the speedometer, amps/volts (can't remember what one it is, shame on me!), and only the speedo gets lit up at night. I added an oil pressure gauge and those are all I have. New dash going in, will have to check it before I install it, and see what I get!

 

[TWR]

My 66 Polara has the same issue. It's put away for the winter but I will be watching this post for the solution.