Set Appliance State:

Mains Power Off
Gas 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:

Apply heating demand, allow fan to start.
After 12 seconds voltage should be present at test points. Measure voltage across the black (neutral) and red(live) leads on connector 4 on the PCB.
Expected voltage approximately 200V DC.
Voltage will only be present for approximately 4 seconds during the ignition phase the appliance will try to ignite a maximum of 5 times before going to lockout.