Troubleshooting - Epson TM-U220 Series Service Manual

Confidential
Table 3-3 ERROR LED Flashes
Probable part/probable cause
CPU execution error
Head high-temperature detection
circuit error
The ERROR LED flashes 3 or 6 times
and then does not operate all.
Rev. B
Checkpoints
Check the connection of the I/F
circuit board unit (122). Make
sure the connector is plugged
into the main circuit board unit
(201).
Check parts on the I/F circuit
board unit (122) for damage.
Make sure the I/F circuit board
unit appears normal.
Check main circuit board unit
(201) parts for damage. Make
sure the main circuit board unit
(201) looks normal.
Check the print head
temperature. Make sure it is not
too high.
Check connection of the head
FFC (521). Make sure it is plugged
into the print head unit (503) and
connector (CN9) on the main
circuit board unit (201).
Check the continuity of the print
head unit (503). Make sure wires
are not broken or shorted out.
Check if main circuit board unit
(201) parts have any damage.
Make sure the main circuit board
unit (201) looks normal.
Check the setting of DIP SW2-6.
OFF: Initial state
ON: Rewriting flash memory.
TM-U220 Type A Service Manual
Action to correct the problem
Connect the I/F circuit board unit
(122). Completed if operation is
normal.
Connect the I/F circuit board unit
(122). Completed if operation is
normal.
Replace the main circuit board unit
(201). Completed if operation is
normal.
Wait for the print head temperature
to drop. Completed if operation is
normal.
Connect the head FFC (521).
Completed if operation is normal.
Connect the print head unit (503).
Completed if operation is normal.
Replace the main circuit board unit
(201). Completed if operation is
normal.
Switch DIP SW2-6 on the main circuit
board unit (201) to OFF. Completed if
operation is normal.
If operation is not normal, rewrite the
firmware. Completed if operation is
normal.

Troubleshooting 3-5