Troubleshooting; Troubleshooting Procedure; Troubleshooting Guide - Citizen PPU-700 Service Manual

4. TROUBLESHOOTING

4.1 Troubleshooting Procedure

When a trouble occurs, confirm its phenomenon, locate a defective part in accordance with "4.2 Troubleshooting
Guide", and troubleshoot as described below.
Find a trouble phenomenon in this column. If there are multiple phenomena, take all the
Phenomenon
corresponding items into consideration. This allows you to specify a hidden defective part.
Lists as many possible causes as possible. Guess a trouble cause out of them and take its
Cause
check method to specify the trouble cause.
Check Method Describes a check method to specify a trouble cause.
Remedy Troubleshoot by taking a remedy described in this column.
By troubleshooting in accordance with the above-mentioned procedure, you can troubleshoot efficiently with fewer
misjudgments.

4.2 Troubleshooting Guide

• Power Supply Failure
Phenomenon
No power
(POWER lamp not
illuminated)
The fuse immediately goes
again after replacing with
a new one.
* If the fuse is gone with the specified AC adapter used, it is likely that the thermal head unit or control PCB assy
is defective. Replace either defective one.
Incidentally, check the wiring of the interface cable.
Cause
The AC adapter is not
connected.
The fuse is gone.
Faulty control PCB assy
The circuit drive power is
abnormal.
Check Method
—
Check whether any
unspecified power has
been used so far.
Check whether the
specified fuse is used.
—
Check the circuit drive
voltage with a DC
voltmeter.
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PPU-700 Service Manual
Remedy
Connect the specified AC
adapter.
Use the specified AC
adapter.
Use the specified fuse.
Replace the control PCB
assy.
Replace the control PCB
assy.