[AdamIsAdam]

Originally Posted by Old Goat 67

That voltage reading is a good way to troubleshoot, but my question is whether that is open circuit or not?

If circuit is open at sender, you should read 12V then. If connected to sender it indicates that sender is flowing current through it.

Hmm. Not sure I'm totally following you here. My understanding is that while the gauge receives 12v in, the lead out of the dash to the sending unit is generally lower than 12v. Regardless, I tested with that lead wire unplugged from the sending unit at the tank and with the key ON. Does that answer your question?