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Hello guys.. Another conundrum here.. My temperature gauge stopped working today for no reason.. I just got in the car like normal and went to go and it doesn't do anything.. I put one of the in dash tachs in a few weeks ago and everything was fine and working like it should and today it just won't work.. Any ideas as to why such a sudden change.. I did get up and crimp the green wire to the coil for the tach a little tighter since it was jumping but other than that I didn't disturb anything else...
thanks,
john
-John
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1966 Dodge Coronet 440 318 Polysphere 727 auto
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With it warmed up shut it off and with ignition on not running watching gauge then wiggle wires at firewall junction and under dash. See if you notice it move. To start with.
The Idaho Andy
I love the smell of race fuel in the morning
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I may have to get someone else to help me watch it since I can't see if it jumps or anything if I'm not looking at it haha
-John
1966 Dodge Coronet 440 318 Polysphere 727 auto
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take your cell phone and see if you can place it someplace it can see the gauge. Then start video recording the gauge while you wiggle the wires. You can play it back and see if it moved
I love Mopars so much I'm date coding the skid marks in my underwear.
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Avenger Wrote:I may have to get someone else to help me watch it since I can't see if it jumps or anything if I'm not looking at it haha
Well placed mirror?
The Idaho Andy
I love the smell of race fuel in the morning
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I hate to get involved here.
You say your temp quit working? You also state you installed a Tach? Is this a aftermarket unit or a factory unit?
The temp and fuel gauges run off a 5 volt limiter that it located on the mother board on the back side of instrument cluster.
If the factory temp gauge stops working, usually the gas gauge quits as well. If gas gauge keeps working? Id look at sender and the wire to sender. If you ground the temp sender wire, the Gauge should "peg"
If both gauges are not working? Id say the limiter has failed.
Classic industries sells a mother board with a solid state 5 volt regulator built into the piece.
The tach is another animal.
Usually a 4 wire deal.
Green goes direct to neg coil.
Black is ground.
Red is 12 volt switched by key
Other color is for Tach back light, sometimes wired to switched by key.
Like I say
I hate to get involved.
And I assume your using the factory gauges and a aftermarket Tach.
I hope this helps
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My gauges, (Fuel and Temp) were "wiggling" back and forth a little and I changed to a solid state unit, end of problem!
Objects quickly DISAPPEAR in the rearview mirror and PLEASE stay seated until the ride comes to a complete stop!!
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Its just the temp gauge that quit..the fuel gauge works just fine...and its an aftermarket tach but its one of the ones that fits in the clock spot and looks like it should be there for a 66-67
-John
1966 Dodge Coronet 440 318 Polysphere 727 auto
