First, don't remove the "For Wizards Only - Do Not Use" warning tape from the
LOAD terminals unless the old GFCI actually has things on its
LOAD terminals. Sometimes a GFCI has 4 wires, but they all go to
LINE. If so, do that!
Then, follow a 2-step process for hooking up any GFCI.
Identify which screws on the new GFCI are the
LINE screws. Usually this can be done simply by not removing the warning tape yet.
There should be a pair of wires from the same cable (usually black and white) which were on the old GFCI's
Attach those "candidate" wires to the
LINE screws. Now, protect the other wires so they won't zap anything. Plug something into the new GFCI. Then, go turn on the power, and test the appliance plugged into the new GFCI. Make sure all that works great.
You can also hit "Test" and "Reset" if you can find a way to do that without touching the stuff and getting zapped.
If the GFCI is not working in all respects, STOP. Do not proceed to step 2. You probably got the wrong set of wires, so turn off the power again and rearrange as needed.
Now, if the old one had any other wires on
LINE, turn off power and hook them up. This should not cause problems but checkpoint this anyway.
Note the wiring on the
LOAD terminals of the old GFCI. If there is any, tear off the warning tape and attach it to the new GFCI's
You know that the work done on the
LINE terminals is solid, so do not mess with that if you're having a problem here. The problem must be something you just did.