Epson Stylus COLOR 440 Service Manual page 88

EPSON Stylus COLOR 440, 640, and 740
Symptoms Condition
(Continued) (Continued)
The printer does not CPU does not operate.
operate at all.
The carriage does not The carriage motor does
operate normally. not operate at all or it
produces an abnormal
noise.
(Continued on the next
(Continued on the next
page.)
page.)
Table 3-6. Unit Repair of Main Board (continued)
Cause Check Point
(Continued) Stylus Color 740:
Control ROM, D-RAM, • If you cannot find a waveform at Pins 2, 128, and 127 of
IC1, the chip is defective.
and Mask ROM are
defective, or are not • If you cannot find a waveform at Pin 85 of IC2, the chip is
defective.
being selected
correctly. • If you cannot find the waveform at 13-pin of IC3, the IC3 is
dead.
• If you cannot find a waveform at Pin 27 of IC4 or IC5, the
respective chip is defective.
• If you can not find a waveform at Pin 14 of IC6, the chip is
defective.
Stylus COLOR 440: Stylus COLOR 440,
640:
CRU2 is defective.
Check the waveform at
Pins 27 and 28 of IC1.
Stylus COLOR 640:
Stylus COLOR 740:
CR2 is defective.
Check the waveform at
Pins 118 and 119 of IC2.
Stylus COLOR 740:
Also, check the output
CR1 or IC2 is defective.
waveform at Pin 91 of
IC2.
IC2 is defective.
Stylus COLOR 440:
Check the waveform at
Pins 25 and 18 of IC14.
Stylus COLOR 640:
Check the waveform at
Pins 43 and 26 of IC14.
Stylus COLOR 740:
Check the waveform at
Pins 27 and 16 of IC11.
Chapter 3 Troubleshooting
Solution
Stylus Color 740:
• Replace IC1.
• Replace IC2.
• Replace IC3.
• Replace IC4 or IC5.
• Replace IC6.
Stylus Color 440, 640:
Replace CRU2 or CR2.
Stylus Color 740:
Replace CR1 or IC2.
Replace IC2.
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