Set Appliance State:

Set Multimeter to AC Voltage Set meter to measure AC Volts
CH Demand
Isolate Mains Power to appliance as per TOPs P4
Mode Switch in LOW position
Gain access to appliance terminal strip
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the Voltage across the Brown spaded wire on the Mode Switch and the connection marked N (connection1) on the main connector block.