Xerox Phaser 7760 Service Manual page 92

A
Check IBT Belt installation (REP 9.22). If the check is good, replace the Engine Control Board
(MCU PWB) (PL 13.1).
Figure 1 004-640 Belt Edge Sensor
Figure 2 004-640 IBT Steering Motor
Status Indicator RAP's
004-640, 004-641
004-641 Belt Edge Not Detected
IBT Belt Edge not detected.
Procedure
Check if actuator for IBT Edge Sensor touches belt edge. IBT Edge Sensor touches belt
edge.
Y N
Check actuator installation.
Turn the printer power On. Measure voltage between I/F PWB P539-A3(+) and GND(-).
Between +3 VDC and 1 VDC is measured.
Y N
Measure voltage between I/F PWB P539-A1(+) P539-A2(-). +5 VDC is measured.
Y N
Close the Front Cover. If voltage between P539-A1(+) P539-A2(-) is less than +5
VDC, replace the Engine Control Board (MCU PWB)
Measure voltage between I/F PWB P539-A3(+) and GND(-). +5 VDC is measured.
Y N
Measure voltage between I/F PWB P539-A3(+) and GND(-). 0 VDC is measured.
Y N
Check wire damage or bad connection between I/F PWB P539A and IBT Edge
Sensor J119.
If the check is good, replace IBT Edge Sensor.
If the problem continues, replace the Engine Control Board (MCU PWB)
13.1).
Check wire damage or bad connection between I/F PWB P539-A3 and IBT Edge
Sensor J119-2.
Replace the IBT Edge Sensor.
Measure voltage between I/F PWB P539-A1(+) and GND(-). +24 VDC is measured.
Y N
Following Wire Network, check +24 VDC circuit up to I/F PWB P539-A1.
Remove IBT Assembly (REP 9.15). Enter
shooting > Service Tools > Printer Status Page > hold the Up and Down buttons simulta-
neously > Run Service Diagnostics > OK. Perform the Steering Motor test. IBT
Motor energizes.
Y N
Check wire damage or bad connection between I/F PWB J537 and IBT Steering Motor
J207. There are broken wires or bad connections.
Y N
Replace the Engine Control Board (MCU PWB)
If the problem continues, replace the I/F PWB
If the problem continues, replace the IBT Steering Motor
Repair broken wire and bad connection.
A
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(PL 13.1).
Service Diagnostics Menu: Printer Menu > Trouble-
(PL 13.1).
(PL 9.1).
(PL 1.3).
Phaser 7760 Color Laser Printer
(PL
Steering
Revised