Set Appliance State:

Mains Power Off
Mode selector switch to Off/Reset position
Set Multimeter to DC Volts Set meter to measure DC Volts
WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the voltage between terminals 1 and 2 at connector M9 on the main PCB. Voltage should be approximately 5 volts DC.
Note:
Ensure probes do not touch together during test.