Set Appliance State:
Set Multimeter to DC Volts 
Turn Hot Water Tap On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Reset boiler as necessary.
Test 1:
During the sparking stage of the ignition sequence measure the DC voltage between the pin 1 (black) and pin 3 (white) leads at the gas valve.
Voltage should be approximately 6V DC.
Test 2:
During the sparking stage of the ignition sequence measure the DC voltage between the pin 2 (brown) and pin 4 (blue) leads at the gas valve
Voltage should be approximately 10V DC.
Note:
1. Boiler may enter lockout during test, reset as necessary until test is complete.
2. Negative voltage may be measured, this is ok as long as voltage is still approximately -6/10V DC.
Test 1:
During the sparking stage of the ignition sequence measure the DC voltage between the pin 1 (black) and pin 3 (white) leads at the gas valve.
Voltage should be approximately 6V DC.
Test 2:
During the sparking stage of the ignition sequence measure the DC voltage between the pin 2 (brown) and pin 4 (blue) leads at the gas valve
Voltage should be approximately 10V DC.
Note:
1. Boiler may enter lockout during test, reset as necessary until test is complete.
2. Negative voltage may be measured, this is ok as long as voltage is still approximately -6/10V DC.
Isolate as per TOPs P4
and refit as necessary