Specifications

Problem
The printer
does not op-
erate at all.
The carriage
operates
abnormally.
REV.-B
Table 5-4. Repair of a Problem in the BOARD ASSY., MAIN (Cont.)
I
Symptom
The CPU does
not operate.
The carriage
does not op-
erate at all.
Carriage oper-
ation is unsta-
ble (lack of
torque).
Cause
Either ROM or
RAM is
defective.
The CPU is
defective.
IClC is
defective.
IC2A is
defective.
IC2A is
defective.
Checkpoint
Check the oscillator signal at either pin 33
or pin 34 of the CPU.
Check the MOTOR, CR phase signal at pins
9, 10, 11, and 12 of ICIC.
I I I I I I I I
At IC2A, check the input signal for pin 90
and the output waveform for pin 100.
Solution
Replace IC5E
Dr IC6E.
If a signal is
detected, re-
place IC 1 C.
Otherwise, re-
place CR 1.
Replace IC 1 C.
Replace IC2A.
Replace IC2A.
5-15