Before Servicing; Diagnosing Failures; Symptoms And Solutions; Chapter 1 Troubleshooting - Epson TM-U675 Service Manual

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Chapter 1
Troubleshooting

Before Servicing

The beginning of this manual (pages vi to viii) provides precautions you should observe to
perform work safely and the necessary information to service this product safely. Always read
that information before starting your work.

Diagnosing Failures

Use one of the following methods to diagnose the area where a failure occurred.
See Table 1-1 for diagnosing the area where a failure occurred by the symptom of the
problem.
See Table 1-2 on page 1-9 for diagnosing the area where a failure occurred from the ERROR
LED code.
See Table 1-4 on page 1-12 when the failure is on the main circuit board unit.
Note:
The explanation of how to use the self test is on page 1-6.
The explanation of power on self checks is on page 1-4.

Symptoms and Solutions

This explains how to find the source of a problem using the symptom. The numbers in the
Solutions column indicate the order to use to check the problem. If you cannot determine the
cause of the problem after checking the first item, proceed to the next number.
Table1-1 Symptoms and Checkpoint
Symptom
Power does not turn on.
Power on self check is not completed.
Or, POWER LED does not light.
There are missing dots in the print.
The print is thin.
Rev.D
TM-U675/U675P (with autocutter) Service Manual
Checkpoints (by Priority)
1. Check the power supply unit. Check that 24V is coming out of
the power supply.
2. Check the main circuit board unit. (See page 1-12.)
3. Unplug the printer. Then unplug each motor or coil's connector
from the main board one by one; plug the printer back in, and
power it on. This will let you know if any motor or coil has burned
out and is pulling down the power. (See page 1-11.)
4. Replace the I/F circuit board. (See page 2-129.)
1. Replace the print head unit. (See page 1-15.)
2. Replace the main circuit board unit. (See page 2-96.)
1. Replace the ribbon cassette. (See page I-8.)
2. Proceed to "Ribbon won't feed" below.
Troubleshooting 1-1