Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the connector from the gas valve
and slide back the black plastic cover
Remove connector X4 from the PCB
and slide back the black plastic cover
Remove connector X4 from the PCB
Measurement:
Test 1:
Measure the resistance between pin 4 on X4 and the blue wire at the gas valve connector.
Test 2:
Measure the resistance between pin 3 on X4 and the brown wire at the gas valve connector.
Expect continuity / zero resistance on each test.
Also visually inspect the condition of the harness and connectors.
Is the resistance measured as expected and the harness in good condition?
Measure the resistance between pin 4 on X4 and the blue wire at the gas valve connector.
Test 2:
Measure the resistance between pin 3 on X4 and the brown wire at the gas valve connector.
Expect continuity / zero resistance on each test.
Also visually inspect the condition of the harness and connectors.
Is the resistance measured as expected and the harness in good condition?
.gif)
Isolate as per TOPs P4
and refit as necessary