Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the two Red wires from EV1 and EV2 and the Blue wire on COM
Measurement:
Check resistance across EV1 and COM is between 700 - 1000 ohms.
Check resistance across EV2 and COM is between 700 - 1000 ohms.
Check resistance across EV2 and COM is between 700 - 1000 ohms.
Isolate as per TOPs P4
and refit as necessary