You'll need:
- 3mm Allen Key
- Multimeter
The machines will need to be completely cool and unplugged to start the process
Remove the bottom panel with the 4 screws marked below. A 3mm Allen Wrench is used
Unplug the wires marked below one at a time, then plug the machine in and turn it on to see if it stops tripping the GFCI
If you have a multimeter you can test the resistance of the element as shown below
