January 2010
2-57
Phaser 7760 Color Laser Printer
004-641, 004-642
Status Indicator RAP’s
Revised
Check IBT Belt installation (REP 9.22). If the check is good, replace the Engine Control Board
(MCU PWB) (PL 13.1).
Figure 1 004-641 IBT Belt Edge Sensor
Figure 2 004-641 IBT Steering Motor
004-642 Belt Edge Not in Position
IBT Belt Edge not in position.
Procedure
Check if actuator for IBT Edge Sensor touches belt edge. IBT Edge Sensor touches belt
edge.
YN
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.
YN
Measure voltage between the I/F PWB P539-A1(+) P539-A2(-). +5 VDC is measured.
YN
Close the Front Cover. If voltage between P539-A1(+) P539-A2(-) is less than +5
VDC, replace the Engine Control Board (MCU PWB) (PL 13.1).
Measure voltage between I/F PWB P539-A3(+) and GND(-). +5 VDC is measured.
YN
Measure voltage between I/F PWB P539-A3(+) and GND(-). 0 VDC is measured.
YN
Check wire damage or bad connection between I/F PWB P539A and IBT Edge
Sensor J119.
If the check is good, replace the IBT Edge Sensor.
If the problem continues, replace the Engine Control Board (MCU PWB) (PL
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.
YN
Following Wire Network, check +24 VDC circuit up to I/F PWB P539-A1.
Remove IBT Assembly (REP 9.15). Enter Service Diagnostics Menu: Printer Menu > Trouble-
shooting > Service Tools > Printer Status Page > hold the Up and Down buttons simulta-
neously > Run Service Diagnostics > OK. Perform the Steering Motor test. IBT Steering
Motor energizes.
YN
Check wire damage or bad connection between I/F PWB J537 and IBT Steering Motor
J207. There are broken wires or bad connections.
YN
Replace the Engine Control Board (MCU PWB) (PL 13.1).
If the problem continues, replace the I/F PWB (PL 9.1).
If the problem continues, replace the IBT Steering Motor (PL 1.3).
Repair broken wire and bad connection.
Check IBT Belt installation (REP 9.22). If the check is good, replace MCU PWB (PL 13.1).
A