Set Appliance State:
Set Multimeter to DC Volts 
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
There is no need to wait for the fan purge to finish before commencing this test.
Measure the DC voltage between the red wire (pin 1) on the 4 way connector at the fan assembly and a suitable earth.
Expect approximately 23 Vdc.
Measure the DC voltage between the red wire (pin 1) on the 4 way connector at the fan assembly and a suitable earth.
Expect approximately 23 Vdc.
Isolate as per TOPs P4
and refit as necessary