Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Disconnect mains in live plug (bottom left)
Disconnect mains in neutral plug (top centre)

Measurement:

Check for continuity (zero resistance) between the L connection at the mains terminal block to the brown wire at the disconnected live plug.
Check for continuity (zero resistance) between the N connection at the mains terminal block to the blue wire at the disconnected neutral plug.
Inspect harness and plugs for good overall condition.