Epson Stylus COLOR 880 Service Manual page 72

EPSON Stylus COLOR 880
Table 3-14. Pump/ASF Motor does not Operate
Step Check Point
1 Getting ready for The CN7 for the Pump/ASF motor is located on the
inspecting Main Board. Using the oscillo scope, check the
waveforms. waveform for each phase output from the indicated
connector. To check the waveform, press the Load/
Eject button to attempt the ASF paper feeding. Be sure
to leave the cable for the Pump/ASF motor connected.
NOTE: The GND can be output by placing the probe
Troubleshooting
Action
C378Main Board
of the oscillo scope to the tapped hole in the
bottom plate on the board with a screw. Note
the connector has no ground line since this
printer drives the motor with the bipolar
system.
Table 3-14. Pump/ASF Motor does not Operate (continued)
Step Check Point
2 Check of the
waveform and
remedies.
Overview
Action
While trying to drive the Pump/ASF motor, the
waveform output from each phase should be as shown
below. If the waveforms output from each phase are as
shown below, replace the Pump/ASF motor. If not,
replace the IC12 (Pump/ASF motor driver IC) or C378
Main Board.
The GND can be output by placing the probe of the
oscillo scope to the tapped hole in the bottom plate on
the board with a screw.
Revision A
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