Set Appliance State:

Use Insulation Mat as required
Set Multimeter to AC Volts Set meter to measure AC Volts
Isolate Mains Power to appliance as per TOPs P4
Selector switch to Water
Lower front panel of control box
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure voltage between connection 4 (white wire) on connector X7 and neutral X4 on the main driver board.