EPSON Stylus Color 900 Revision C
Troubleshooting Overview 90
3.1.2 Isolating the Faulty Part on the Power Supply Board
This section explains how to troubleshoot the following problems:
The printer is turned on, but the initialization is not performed and
LED on the control panel do not come on.
Problems after power on
Be sure to perform troubleshooting in the order specified, because the
parts involved are mentioned in the disassembly procedure to facilitate
servicing.
Table 3-17. Isolating the Faulty Part on the Power Supply Board
Table 3-18.
Isolating the Faulty Part on the Power Supply Board (continued)
Step Check Point Action
1 Is the panel FFC
disconnected from the
connector on the panel
board?
The power switch for this printer is in the secondary
side. Therefore, if the FFC does not transfer
signals, the printer does not operate despite the
power supply board and the main board are
properly connected.
2 Is the panel FFC
disconnected from the
connector (black, 12-
pin) on the relay board?
This printer uses the power switch on the
secondary side. Therefore, if the FFC does not
transfer signals, the printer does not operate
despite the power supply board and the main board
are properly connected.
3 Is the connector
disconnected from the
CN15 on the main
board?
The reason is the same as above.
The panel control FFCs are connected via 1) CN15
on the main board
→
2) Relay board
→
3) Control
Panel.
4 Has the fuse (F1) on
the power supply board
blown?
Check if the line in the F1 located beside the CN1
on the power supply board has blown.
5 Is CN2 or CN3 on the
power supply board
disconnected?
Check that the connectors CN2 and CN3, which
are used to apply power to the main board, are
properly connected.
Step Check Point Action
6 Is CN 5 or CN6 on the
main board
disconnected?
Check that the connectors CN5 and CN6, which
are used to input power from the power supply
board, are properly connected.
7 Is the choke coil
broken?
Viewing the reverse side of the power supply
board, check for the proper continuity at the two
points indicated in the figure below.
8 Is the transformer (T1)
broken?
Referring to the figure below, check if the
transformer is disconnected between the poles. Try
every combination in each group marked with a
blue box.
L1 (reverse side)
CN1 side
CN2 side
CN5 Side
CN3 Side
T1
(reverse side)
