Set Appliance State:
Mains Power Off
Set Multimeter to AC Volts 
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Measure the voltage at connection 10, marked SL (brown lead) and connection 9, marked N (blue lead) on the bottom connector of the PCB.
Isolate as per TOPs P4
and refit as necessary