Set Appliance State:

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

Measurement:

Measure resistance between Brown and Blue connections plug X16 on the Motherboard.
Resistance should lie should be in the range 40-60 ohms.
Measure resistance between the Blue and Black wires at plug X16 on the Motherboard.
Resistance should lie should be in the range 40-60 ohms.