Voltage regulator for fuel sending unit . . . Mine appears to be defective. I know it sits on the back of the instrument cluster. Wondering how it's removed and where I can get a new one from.
I have one I don't need. PM me if you're interested in it. I thought mine was defective because the output side wasn't showing any voltage and I ordered a new one. Turned out to be a short in the wire going to the sender, The short was bleeding off the voltage. Suggest you check the output voltage with the wire to the sender removed. I hear the regulators rarely fail. Mine didn't fail even with a dead short.
we removed the harness off the sender and jumped it and nothing happened. When the sender is attached to the harness it goes past full when I turn on the car. So where do I check for voltage?
Ground My 72 Grabber gauge go beyond full; but, will some times move. My best guess the ground to the sender. Resently, I replaced the starter to a late model small one. The old starter worked just fine; but, the new one would just lick once. I added a ground wire to the neg cable and the fender, then it started fine. I have not had time to check my other grounds. Rick
Sounds just like my symptoms. A short will push the needle past full with a working regulator. Think you should pull the instrument cluster out, find the regulator on the circuit board in back. The '72 version is easy to spot -- it has 9V battery style connectors. When I checked the voltage on the output terminal with wire attached, it read near 0 volts. Pulled the wire and it jumped around (that's normal) showing a few volts. If you see that I bet your regulator is good and you have a short. If you have a short you can isolate it some by disconnecting connectors. Pull the one off the sender. If the gauge goes to E, I guess you have a bad sender. If it still reads past full, pull the connector at the frame by the gas tank. (Maybe its in the trunk?) If the gauge goes to to E, the short is between that connector and the one on the sender. If it still reads past full, the short is between the frame-side connector and the regulator connector.
here is what I got: at the voltage regulator with the wire harness attached it read somewhere around 0.3-.45 volts and it was jumping around. there was no voltage reading at the regulator with the harness removed.
Don't know what to say about that. Your needle pegs when harness is attached but regulator isn't putting out any voltage. Seems inconsistent. Guess I'd check resistance between the detached wire at the regulator and ground just to be sure there's no short. If none, I'd replace the regulator. They aren't that expensive. Well, most aren't. I saw some for $70 but paid about $30 for mine as I recall. If you buy an original style regulator, check to see that the pos and neg connectors are oriented the same as yours. Most I looked at were reversed. I bought an electronically regulated one that mounts away and has pigtails with the 9v style terminals.
