I disconnected the sending unit, and was going to ground the lead that attached to it using a 10 ohm resistor. I turned the ignition to the ON position and the gauge pegged out. I grounded it and there was no change, but when I plugged the sensor back in, it stopped reading again. What caused this, is the wire lead already grounded somewhere?

Also, I want to test to see if the temp gauge is receiving voltage, anyone know which lead or leads on the wiring harness to touch w/voltmeter to determine this? Oh yeah, this is a 92 Explorer.

Thanks,

Phil

 

Okay Read this!
I copied this from one of my files.
Some procedures might have already been done by you.

To check the gauges with the key off:
Take the connector for the temperature sending unit off
put a cotter pin it, now attach it to a good ground,go back and turn the key to ON > If the gauge pins to the high side the gauge is good.


Now do the same with the gas gauge sending unit.


If the gauge DON'T pin, there is either something wrong with the gauge,wiring,or IC V reg.

To check the IC V.Reg with key ON:
Take a test light and attach it to the sending units wiring.
You should have a PULSING light.
If so, the IC V. reg is Okay.

If Not,either the wiring is bad or the V reg. is bad.
The IC V.reg is located on the back of the Instrument cluster.


So,If you have a gauge that Pins and a Connector that Pulse flashes : the problem is with the sending unit.

Check the S.U. for teflon tape wrapped around the threads.
If so,remove it and check it again for gauge reading.

Alwats use the proper sealant for sending unit threads.
Teflon tape is insulator
You need a conductor sealant.




[i][font color=blue]Dennis[/font][i]

[font color=red]Calgary,Alberta,Canada[/font]
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[font color =green] Please Don't Ask Me Any Tough Questions,
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[font color=blue]78 F-150 429CJ,Silver,Explorer Pkg.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
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84 Volvo DL Wagon [/font]

 

Thanks for the advice! I have tried both gorunding the gauges directly and using a test light, neither seems to work. I then tried using the test light on my oil gauge lead, and it didn't wok for that either ... I am using a 6v/12v test light and usually ground to the frame rail. Is there a better place to ground it? Anyone have an idea of why the fuel gauge pegs simply from being disconnected?

Thanks,

Phil

 

The original explaination didn't sound like it said that.

It means the wire to the gauge is grounded between your SU and the gauge.

Sorry to tell you.
You going to have to pull the cluster out to check the ICVR
amd the printed circuit on the cluster.

Take a meter and do a continuity test between fuel SU and ground.


[i][font color=blue]Dennis[/font][i]

[font color=red]Calgary,Alberta,Canada[/font]
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[i][font color=green]
http://www.clubfte.com/users/mil1ion/Mil1ion.html [/font][i]

[font color =green] Please Don't Ask Me Any Tough Questions,
"I'm Saving My Memory For When I Develop Alzheimer's" [/font]


[font color=blue]78 F-150 429CJ,Silver,Explorer Pkg.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon [/font]