Epson DFX-8500 Service Manual page 190

DFX-8500
5.2.2 C204 MAIN/DRV/DRV-B Boards Repair
Table 5-6 indicates major components which is used for the C204 MAIN/DRV/DRV-B boards and Table 5-7
shows the C204 MAIN/DRV/DRV-B boards component level troubleshooting.
Table 5-6. C204 MAIN/DRV/DRV-B boards Component Repair 1/7
Symptom
The printer does The DRERR signal
not operate at all. was sent to the C204
power supply board
(HIGH level turns off
the power supply).
The PD signal was
sent to the C204
power supply board.
(HIGH level turns off
the power supply)
The reset circuit is not
operational (for logic).
The driver circuits The pull up voltage
don't operate at VX is not generated.
all.
Serial interface is The level converter IC
dead. is defective.
5-16
Cause
Check the logic level of the DRERR
signal at CN10 or check the VP1 and
VP2 voltage.
Check the logic level of the PD signal
during power on and verify the voltage
waveform for the head driver. (Refer to
the head driver waveform figure,
above.)
Check the logic level at pin1 (VOUT) of
IC13.
When the collector of Q15 is high
Check the logic level at collector of Q14
(VX) (When the collector of Q15 is
high, VX is HIGH..
Check the signal level change between
in and out port of the IC9.
Checkpoint Solution
Replace the head
driver on the C204
MAIN board (VP1)
or C204 DRV-B
board (VP2).
Replace the head
driver or gate array.
Replace IC13.
Replace Q15.
Replace IC9.
Rev. B