Service manual

SERVICE MANUAL MASTER FILE
ENGLISH
Rev. A (1997/05/07)
3-11
.3 UNIT REPAIRING OF THE POWER SUPPLY BOARD
This section is necessary only for servicers who repair to the component level. Servicers who
perform only board replacement can ignore this section.
The table below lets you troubleshoot problems with the power supply board (C229PSB/PSE). The
table provides various symptoms, likely cases, and checkpoints. Checkpoints include waveforms,
resistance, and other value to be checked to evaluate the operation of each component.
Table 3-6. Repair of the C229PSB/PSE
Symptom
Condition Cause Checkpoint Solution
Fuse F1 is
blown.
Verify whether the fuse is blown or
not.
Replace the
C229PSB/
PSE board.
Transformer
(T1) is open.
Verify the coil of transformer by a
multimeter.
Replace the
C229PSB/
PSE board.
The printer
dose not
operate at
all.
+35V line is
defective.
Switching
FET (Q1) is
defective.
Verify the waveform at drain of Q1.
Figure 3-10. Drain of Q1
Replace the
C229PSB/PS
E board.
Q2 or Q3 is
defective.
Verify the waveform at corrector of
Q2 or Q3.
Figure 3-11. Corrector of Q2/Q3
Replace the
C229PSB/
PSE board.