Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect wires from connections
marked 3 and 5 on the internal timer

Measurement:

Check for continuity (zero resistance) between each of the disconnected wires to the corresponding wire at M5 on the PCB.
Inspect the harness and connectors for good overall condition.