Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove ignition PCB from gas valve and remove cover,
leave connectors in place
Remove speed control connector from fan assembly

Measurement:

Test 1. Measure for continuity (short circuit) between pin 1 (X8 PCB)
and yellow lead removed fan connector.
Test 2. Measure for continuity (short circuit) between pin 5 (X8 PCB)
and red lead removed fan connector.
Test 3. Measure for continuity (short circuit) between pin 9 (X8 PCB)
and green lead removed fan connector.
Note.
Due to the small size of the connectors used on this appliance, harness checks are carried out from PCB connections.