Set Appliance State:
Gas Off
Set Multimeter to Resistance 
Isolate Mains Power to appliance as per TOPs P4
Disconnect the Main PCB Connector marked PL3 from the PCB
Disconnect the Main PCB Connector marked PL3 from the PCB
Measurement:
Allow the Air Flow Sensor to cool.
Measure the resistance across the Green wire (marked A2)
and the Red wire (marked A1).
Repeat the measurement using the Black wire (marked A3)
and the Red wire.
The resistance obtained for both measurements should be
between 7 and 30 ohms.
Replace connector after test.
Measure the resistance across the Green wire (marked A2)
and the Red wire (marked A1).
Repeat the measurement using the Black wire (marked A3)
and the Red wire.
The resistance obtained for both measurements should be
between 7 and 30 ohms.
Replace connector after test.
Isolate as per TOPs P4
and refit as necessary