Oki OL1200 Service Manual page 169

Is the printer recovered?
YES END.
No Is the heater or thermistor open?
Measure the resistance between the heater contacts (normal resistance: 220 kW
(25°C) between pins 1 and 2, 2.3 W (120 V) and 8.5 W (240 V) between pins 3 and 4)
(See chapter 7.3.)
Yes
No Is the AC voltage applied to the CN2 connector on the Power/sensor board? (See Fig.
4.)
No
Yes
Yes
YES Go to B.
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No Replace the Power/sensor board or Control board.
Replace the fuser unit.
Is CN2 connector connected to the Power/sensor board?
No Connect the CN2 connector to the Power/sensor board properly.
Is Pin 31 (HEAT ON signal) of the POWER connector of the Control board turned
on? (In normal state, this pin is set to 0 V).
No Replace the Control board.
Replace the Power/sensor board.