Set Appliance State:

Set Multimeter to AC Volts Set meter to measure AC Volts
ECO mode ON
Ensure NO demand
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:


While measuring for AC voltage across connector ST4 on the PCB, expect mains voltage, press and hold the reset button for at least 5 seconds then release, voltage should drop to zero.
Note:
Following the set-up instructions for this test is critical for correct diagnosis. Failure to turn off the preheat function or failure to remove any other demand will result in misdiagnosis.