Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove connector for DHW flow turbine
Pull connector X8 back slightly to expose test points
Pull connector X8 back slightly to expose test points
Measurement:
Measure the resistance of each wire of the harness.
The resistance should conform to the table below:
Inspect harness and connectors
for good overall condition.
The resistance should conform to the table below:
| Wire | Resistance in Ohms | Red - Red (pin 10) | Continuity (zero resistance) |
| Blue - Blue (pin 9) | Continuity (zero resistance) |
| Black- Black (pin 8) | Continuity (zero resistance) |
Inspect harness and connectors
for good overall condition.
Isolate as per TOPs P4
and refit as necessary