Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the connector from the Aqua sensor
Remove connector X2 from the PCB
Remove connector X2 from the PCB
Measurement:
Measure the resistance of each of the wires in the aqua sensor harness as stated in the table below.
Expect continuity / zero resistance on each of the wires.
Also visually inspect the harness for good general condition.
Note:
Each pin on the PCB connector is numbered.
| Pin on connector (X2) | Aqua Sensor Connector | 3 (Red) | Red |
| 2 (Black) | Black |
| 6 (Green) | Green |
Expect continuity / zero resistance on each of the wires.
Also visually inspect the harness for good general condition.
Note:
Each pin on the PCB connector is numbered.
Isolate as per TOPs P4
and refit as necessary