Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Remove connector X1A from the PCB
Measurement:
Measure the resistance between pin 2 (black) on the mains
terminal block to the black wire on connector X1A.
Expect continuity / zero resistance.
terminal block to the black wire on connector X1A.
Expect continuity / zero resistance.

Isolate as per TOPs P4
and refit as necessary