Set Appliance State:

Set Multimeter to Resistance Set meter to measure resistance
Isolate Mains Power to appliance as per TOPs P4

Measurement:

Pull off leads from microswitch SW3
(grey connector, left hand switch).
Measure resistance of SW3.
HW Tap Off.
Top and middle terminals = open circuit.
Top and bottom terminals = short circuit.
HW Tap On.
Top and middle terminals = short circuit.
Top and bottom terminals = open circuit.