I moved into a new house recently. One of the outlets was a 2-prong, ungrounded receptacle. I wanted to install a GFCI so I could plug in 3-prong devices.
The old receptacle had 2 hot, 2 neutral and no ground wire. I tested with a multimeter to identify the line and load pairs and wired them into the GFCI.
Once I energized the circuit, the GFCI would not reset. If I remove just the load wires, the GFCI will reset and function.
I'm trying to figure out what could be the source of the problem. The downstairs bathroom appears to be on the same circuit and also has a GFCI. I can reset that GFCI no problem.
It appears to be downstream of the newly installed GFCI. Could the two be interfering with each other?