Troubleshooting By Symptom - Epson MX-80 Technical Manual

3.4.2 Troubleshooting by symptom
SYMPTOM 1
The printer does not operate nor any indicator on the control panel lights when the power
switch is turned on.
No.
Cause of Trouble Check Point Repair Method
1 Blown fuse
eCheck the fuse and filter circuit board elf blown, replace the fuse with
to see if the fuse has blown out. a new one.
elf the newly inserted fuse still
blows out. the cause of trouble
exists in other parts. Check
items 2 and 3 below.
2 Defective fuse and filter cir- elf the fuse is normal. disconnect the eln the absence of the proper
cuit connector on the primary side of the primary voltage, replace the
power transformer and check with a
fuse and filter circuit board
tester if 115,220 or 240VAC is present with a new one. See paragraph
between pin Nos. 1 and 5. 3.32 (4) for replacement.
3 Defective power
elf the primary AC voltage is normal, dis-
eln the absence of proper sec-
transformer connect the connector on the second-
ondary voltages, replace the
ary side of the power transformer and defective power transformer.
check with a tester for proper second-
See paragraph 3.3.2 (3) for
ary voltages.
replacement.
Voltage between pins 1 and 2: 10VAC
Voltage between pins 3 and 4: 25VAC
Voltage between pins 5 and 6: 10VAC
Voltage between pins 7 and 8: 16VAC
SYMPTOM 2
None of the indicators on the control panel lights although the secondary voltages of the power
transformer are normal.
No. Cause of Trouble Check Point
Repair Method
1 Broken signal line between
eCheck the
9
respective lead wires eRepair the broken lead wire
the control panel and con- extending from the control circuit board with a soldering iron.
trol circuit board
to the control panel, for any broken
lead.
White Gray Purple Blue Yellow Orange ReO Brown Black
I I II I I I I I I I I I I
II I I
REV. A
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