Citizen CT-S651 Series, Service Manual

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CT-S651 Series Service Manual
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2-3. Troubleshooting Procedure
When a fault occurs, confirm its phenomenon, locate the problem in accordance with “2.2 Troubleshooting
Guide”, and troubleshoot it as described below.
Phenomenon
Find the fault phenomenon in this column. If there are multiple phenomena, take all the applicable
items into consideration. This will help you locate hidden problems as well.
Cause
Possible causes are listed here. Find probable causes from the list and follow the check method to
identify the cause of the fault.
Check Method The check method for identifying the cause of the fault is described.
Remedies Take the remedies described in this column.
By following the above-mentioned procedure, you can troubleshoot problems efficiently with fewer
misjudgments.
2-4. Troubleshooting Guide
● Power Supply Failure
Phenomenon Cause Check Method Remedies
The power cable is not
connected.
−
Connect the power cable. Power cannot be turned
on.
(The POWER LED not
illuminated.)
The fuse is blown. Check if the specified fuse is
used. Use the specified fuse.
The control PCB is faulty.
−
Replace “SA, MAIN PCB”. The fuse is blown soon if
it is replaced with a new
one.
The circuit drive power is
abnormal. Use a tester and measure
the circuit drive voltage. Replace “SA, MAIN PCB”.
* If the fuse is blown with the specified AC adapter used, the thermal head or control PCB may be defective. Replace
the defective part with a new one. Check wiring of the interface cable.