Oki B 4100 Maintenance Manual page 314

ACTION Item:
No.
16 Check item 1:
17 Probable cause 1:
Check item 1:
Probable cause 2:
Check item 2:
40055101TH Rev.4
Check the PWM waveform of CH (cycle: 42 s, ON time: 36 s).
D1 is detective.
Check if both D1 and T1 or D1 and T2 are shorted.
The D1 drive circuit is defective.
Check PC1. [Whether PC1 turns ON or OFF according to the level of HEAT signal
(CN3-B7)?]
Check if R2 or R3 is in open state (This cannot be observed from the external
appearance because these resistors are fusible resistor.)
ACTION
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