Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove pump cover and disconnect electrical connections

Observation:

Test 1:
Measure the resistance between the brown (Live)
and blue (Neutral) connections of the pump.
Expected resistance approx. 165 ohms or greater.
Test 2: Resistance to Earth
Measure the resistance between the brown (Live)
and Earth connections of the pump.
Expected resistance greater than 1 MOhm.