Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to Resistance Set meter to measure resistance
Remove wiring connections at pump

Measurement:

Test 1:
Measure the resistance across the Live and Neutral terminals.
Expected resistance 180 ohms or greater.
Test 2:
Measure the resistance across the Neutral and Earth terminals.
Test 3:
Measure the resistance across the Live and Earth terminals.
On test 2 and test 3 expected resistance greater than 1 Mohm.
Note.
A reading of O.L on test 2 and test 3 is acceptable as
this is greater than 1 MOhm.