DodgeCharger.com Forum

Mopar Garage => Electric, Gauges, & Lights => Topic started by: svalkid on August 11, 2014, 03:53:42 PM

Title: fuel gauge diagnosis confirmation anyone?
Post by: svalkid on August 11, 2014, 03:53:42 PM
'72. Fuel gauge didn't work when I got the car. Then suddenly sort of worked. Now it doesn't again.
With tank full I have .07 ohms of resistance from sending unit stud, to ground.
With a test light, I have a dim light when checking from sending unit stud, to the wire from the gauge.
Sounds like from what I have been reading, I have a bad fuel gauge.
Whatcha think?
Title: Re: fuel gauge diagnosis confirmation anyone?
Post by: A383Wing on August 11, 2014, 03:55:37 PM
what does the sending unit OHM's read when tank is empty?
Title: Re: fuel gauge diagnosis confirmation anyone?
Post by: svalkid on August 11, 2014, 04:02:01 PM
Have not checked it empty yet.
Title: Re: fuel gauge diagnosis confirmation anyone?
Post by: A383Wing on August 11, 2014, 05:42:27 PM
I would suggest getting a service manual and following the instructions in there for fuel gauge issues...

note: you cannot properly diagnose a fuel gauge or sender problem with a "test light"
Title: Re: fuel gauge diagnosis confirmation anyone?
Post by: fy469rtse on August 12, 2014, 05:30:52 AM
I would check the earth if you got some life out of it, or like its been said go to the service manual  :2thumbs:
Title: Re: fuel gauge diagnosis confirmation anyone?
Post by: John_Kunkel on August 14, 2014, 03:03:28 PM

The sender spec is 10Ω full and 73Ω empty. If you want to check the gauge with an unknown quantity in the tank, place a 73Ω resistor between ground and the sender wire at the tank...gauge should read empty.

Half way on the gauge is 23Ω.