Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove the plug X20 from the PCB and
the connector from the fan

Measurement:

Measure the continuity of the fan harness from the
disconnected connector X20 to the disconnected fan connector.
Black to black.
Red to red.
Grey to grey.
Blue to blue.
Expect continuity on all leads.