Set Appliance State:
User Control to Off Position
Set Multimeter to DC Volts 
Isolate Mains Power to appliance as per TOPs P4
Gain Access to PCB
Gain Access to PCB
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure voltage across connection 1 (red lead) and connection 12 (yellow lead) on connector marked CN3 Display on the main PCB.
Expected voltage between 22 and 30 volts DC.
Expected voltage between 22 and 30 volts DC.
Isolate as per TOPs P4
and refit as necessary