Set Appliance State:

Set Multimeter to Resistance Set meter to measure resistance
Isolate Mains Power to appliance as per TOPs P4
Disconnect ignition control box from the gas valve.
(With ignition control box cover removed, pull control box forward)

Measurement:

Measure resistance across the exposed terminals of EV2,
(positive probe to the top terminal and negative probe to the
terminal on the R/H side of the four terminals exposed).
Resistance should be approximately 850 Ohms.