Repair Of The C172 Psb/Pse Board At Component Level - Epson STYLUS 3000 Service Manual

Troubleshooting

5.3 Repair of the C172 PSB/PSE Board at Component Level

This section contains information which enables you to repair and replace the components on the
electrical board (C172 PSB/PSE). Table 5-5 lists the potential causes for each symptom in order of
possibility, with which you are able to find and repair the defective part.
Table 5-5. Component Repair of the C172 PSB/PSE Board
Symptom Condition
The printer +42 VDC is
does not not output.
operate at all.
+5 VDC is
not output.
5-10
Cause
Fuse (F1) is Check visually if the fuse is good. Replace the fuse F1.
open.
Transformer Check the transformer using a
(T1) is open. multimeter.
Q1 is dead. Check the waveform at drain.
Q2 or Q3 is Check the waveform at corrector.
dead.
PC1 is dead. Check the voltage in lowering at
the Pin 5 or 7.
L4962 is dead. Check the reference waveform
at the Pin 5.
Check the output waveform at the
Pin 7.
Checkpoint
Waveform (1)
Waveform (2)
Waveform (3)
Waveform (4)
Waveform (5)
Solution
Replace the
transformer T1.
Replace the Q1.
Replace the Q2 or Q3.
Replace PC1.
Replace the L4962.
Rev. A