Epson FX-870/1170 User Manual

Page 150

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

pin 27 or

If the signal is

defective.

pin 28).

not correct,
replace

Otherwise,
replace

Carriage

The

IC6 is

Check the input signal (pin 5) and the output

Replace IC6.

operation

carriage

defective.

waveform

8).

abnormal.

does not
operate at
all.

Epson

6-35