Set Appliance State:

Mains Power Off
Set Multimeter to DC Volts Set meter to measure DC Volts
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the DC voltages between each of the test points at connector X51 on the back of the display PCB as listed below to a suitable earth point.
The Voltages should conform approximately to the table below:
Test pointDC Volts
GND0
RES_SW 4.7
EBUS21.8
5V5
24V24
PEBUS5