Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set multimeter to diode mode
Click here for how to set multimeter to diode mode
Disconnect M7 from the PCB

Measurement:

Place black probe on the white wire on M7 and the red probe on the green wire on M7.
Voltage should be approximately 1.8V DC.
Note:
LED may also be seen to illuminate faintly.