Epson FX-870

Principles of Operation
Table 6-8. Repairing the C094 MAIN Board Assembly (Continued)
Problem Symptom
Cause
Checkpoint
Solution
Abnormal
The CPU
operation at does not
power on.
operate
properly.
The CPU is
Check the oscillator signal (IC2Cl pin 27 or
If the signal is
defective.
pin 28).
not correct,
replace
IC2Cl.
Otherwise,
replace CRl.
Carriage
The
IC6 is
Check the input signal (pin 5) and the output
Replace IC6.
operation
carriage
defective.
waveform (pin, 8).
abnormal.
does not
operate at
all.
Epson FX-870/1170
6-35