Xerox Phaser 7760 Service Manual page 420

OF 99-3 Switch
Procedure
Actuate the Switch. The display changed.
Y N
There is +3.5/+5 VDC measured between Pin 2(+) of the Switch and GND(-).
Y N
Check the wire between the switch Pin 2 and the PWB Pin 3 for an open circuit and
poor contact. If the check is OK, replace the PWB.
There is +3.5/5 VDC measured between Pin 1(+) of the Switch and GND(-).
Y N
Replace the Switch.
Check the wire between the PWB Pin 4 and the switch Pin 1 for an open circuit and poor
contact. If the check is OK, replace the PWB.
De-actuate the Switch. The display changed.
Y N
Disconnect the connector on the Switch. The display changed.
Y N
Check for a short between the switch Pin 2 and the PWB Pin 3. If the check is OK,
replace the PWB.
Replace the Switch.
Replace the Switch.
Figure 1 OF 99-3 Switch
Status Indicator RAP's
OF 99-3, OF 99-4
OF 99-4 Generic Solenoid/Clutch
Solenoids and electric Clutches are essentially electromagnets. Typically, a positive voltage is
applied to one end of a coil, and a current driver is connected to the other end. Control Logic
switches this driver to GND potential, actuating the magnet. Bi-directional solenoids have a
bipolar driver connected to each end. One leg is switched to 24 VDC and the other to GND.
Figure 1 is a circuit diagram of a typical Solenoid.
Initial Actions
Ensure that there is no damage or binding in the solenoid or in any mechanical linkage. If there
is an Adjustment for the clutch or solenoid, make sure that the procedure was performed cor-
rectly
Procedure
The Clutch/Solenoid is always energized.
Y N
Enter Service Diagnostics
Printer Status Page >hold the Up and Down buttons simultaneously > Run Service
Diagnostics > OK. Perform the Clutch or Solenoid tests. The
energizes.
Y N
There is +24 VDC between the switched leg (J543 pin A6 in the example,
ure 1) of the control PWB and GND.
Y N
There is +24 VDC between the powered leg (J543 pin A7 in the example,
Figure 1) of the control PWB and GND.
Y N
Disconnect the connector (J543 in the example,
VDC between the powered leg of the control PWB and GND.
Y N
Refer to the 24 VDC wirenets. check the input power to the control
PWB. +24 VDC is present.
Y
Replace the control PWB.
Check the wire in the powered leg of the circuit, (J543 pin A7 in the exam-
ple, Figure
Board (MCU PWB) Plug/Jack Locations -
replace the clutch or solenoid.
Disconnect the connector (J543 in the example,
through the two wires and the Clutch or Solenoid. There is less than 100
ohms between the two legs of the circuit.
Y N
Disconnect the Clutch or Solenoid. Check continuity through the two wires
and the Clutch or Solenoid. There is less than 100 ohms across the
clutch or solenoid.
A B C D
January 2010
2-384
Menu: Printer Menu > Troubleshooting > Service Tools >
Figure
N
Use the 24 VDC wirenets to troubleshoot the problem.
1) for a short circuit to GND (refer to Section 7, Engine Control
Figure
Figure
Phaser 7760 Color Laser Printer
Clutch or Solenoid
Fig-
1). There is +24
15). If the wire is OK,
1). Check continuity
Revised