Test Points On The Main Circuit Board Unit - Epson TM-U220 Series Service Manual

Confidential

Test Points on the Main Circuit Board Unit

Table 3-30 Test Points on the Main CIrcuit Board Unit
Power supply
Power supply
Logic circuit power
supply
Mechanism power
supply
Drawer power
supply
Rev. B
Pin name
Semiconductor switch on —
Semiconductor switch off —
Logic circuit power
supply
Logic circuit power
supply (GND)
Autocutter (117) power
supply
Print head power supply
Roll paper cover open
sensor (515) power
supply
HP sensor (518) power
supply
NE sensor (1096) power
supply
RE sensor (514) power
supply
—
Test
Status
connector
—
—
— —
— —
— —
— —
Cover opened —
Cover closed —
On home position —
Not on home —
position
Sufficient roll paper —
installed
Sufficient roll paper —
not installed
Roll paper installed —
Roll paper not —
installed
— —
TM-U220 Type A Service Manual
Component
connector
U9, pin 3 or pin 4
Q1, pins 5 or 6 or
7 or 8
U9, pin 5
Bottom
assembly frame
F3
Q7, pins 5 or 6 or
7 or 8
CN4, pin 5
CN4, pin 2
CN6, pin 1
CN4, pin 4
CNC3, pin 5
Troubleshooting 3-21
Correct
value
5 V
24 V
3.3 V
0 V
24 V
24 V
3.3 V
0 V
0 V
3.3 V
3.3 V
0 V
0 V
3.3 V
24 V