DodgeCharger.com Forum

Mopar Garage => Electric, Gauges, & Lights => Topic started by: pontiac charger on September 30, 2016, 12:13:54 PM

Title: fuel gauge Power question
Post by: pontiac charger on September 30, 2016, 12:13:54 PM
I have a 68 charger and my fuel gauge quit working.  Before I pull the sender from the tank, I want to confirm it is not the Gauge itself.  So here are my questions

Where do the gauge get power? 
Is it fused at all? 
With the ignition on and a test light on the power wire in the trunk should there be a reading?

Finally, what is the best way to test the gauge?

Thanks for the help and maybe a few less headaches on this.
Title: Re: fuel gauge Power question
Post by: John_Kunkel on September 30, 2016, 01:29:30 PM

All gauges except the ammeter get their power from the instrument voltage regulator (IVR) which reduces 12V to around 5V. If the temp and oil pressure gauges still work, the IVR is OK.

Best way to isolate the tank sender is to remove the wire from the sender and ground it to a known good ground,  then turn on the ignition switch and watch the gauge; it should climb to FULL. If the gauge is OK, next check that the sender is grounded through the snap-on connector between the fuel line and the sender nipple, they are often missing or making poor contact.

If that all checks OK, the sender is bad.
Title: Re: fuel gauge Power question
Post by: pontiac charger on September 30, 2016, 03:35:21 PM
Thanks a bunch for the advice.  I will check all of that out this weekend.