Oki B4100 - Manual (Page 314)

40055101TH Rev.4 314 /
ACTION Item:
No. ACTION
16 Check item 1: Check the PWM waveform of CH (cycle: 42
µ
s, ON time: 36
µ
s).
17 Probable cause 1: D1 is detective.
Check item 1: Check if both D1 and T1 or D1 and T2 are shorted.
Probable cause 2: The D1 drive circuit is defective.
Check item 2: 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.)