Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Turn Hot Water Tap On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset the appliance if required.
(Press reset button once then release)
Allow self check to complete.
Measure the DC voltage between pin 1 on connector CN19 on the PCB to a suitable earth point.
Expected voltage approx. 120 VDC or less.
(Press reset button once then release)
Allow self check to complete.
Measure the DC voltage between pin 1 on connector CN19 on the PCB to a suitable earth point.
Expected voltage approx. 120 VDC or less.
Isolate as per TOPs P4
and refit as necessary