Posted by Paul on August 20, 1999 at 18:13:36:
In Reply to: Testing an M-37 Sending Unit??? posted by Dan G. on August 20, 1999 at 09:48:25:
{{Trying to test the sending unit out of the truck. I think I need to ground the sending unit, feed 24V+ to the gage, feed the other side of gage to send unit. Have I got it right??? Thanks}}
Are you testing the fuel gauge sending unit? The best way to do this is with an ohm meter. Hook the positive lead to the electrical connection and the negative to the body or float arm. Make sure there's no rust on it. If there is, clean it.
All you do now is move the float slowly from the full position to the empty position. The ohm reading should slowly change as the arm moves. If it drops suddenly or goes all the way to infinite (open circuit) your resistor wire is broken.
Once you do this, try hooking up the gauge itself to see how accurate it is. If it's broken though, you won't need to worry about it.