Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the 4 wire connector from the fan
Measurement:
Test1:
Measure the resistance between the following pins:
The resistance should conform approx to the table below:
Test2:
Measure the resistance from each pin on the fan to earth in turn.
Expect Open Circuit for Each Test
Note: This test is carried out with the fan in place.
Measure the resistance between the following pins:
The resistance should conform approx to the table below:
| Pins | Resistance | 2 and 5 | 34kOhms |
| 4 and 5 | 16kOhms |
| 2 and 4 | 50kOhms |
Test2:
Measure the resistance from each pin on the fan to earth in turn.
Expect Open Circuit for Each Test
Note: This test is carried out with the fan in place.
Isolate as per TOPs P4
and refit as necessary