Xerox Phaser 4500 Service Manual page 174

Troubleshooting Procedure (Continued)
Steps Actions and Questions
4 Check the power to No Paper Sensor:
1. Remove the Print Cartridge.
2. Measure the voltages across P/J24-6
<=> P/J24-7 and P/J24-1 <=> P/J24-2
on the HVPS/Engine Logic Board.
Do the voltages measure 3.3 VDC?
5 Check the Chute Assembly Harness:
1. Disconnect P/J24 from the HVPS/
Engine Logic Board.
2. Disconnect P/J245 and P/J248.
3. Test the harness for continuity at these
points:
J24-6 <=> J245-13
J24-7 <=> J245-12
J24-8 <=> J245-11
J24-1 <=> J248-5
J24-2 <=> J248-4
J24-3 <=> J248-3
Are all the conductors continuous?
6
Check the Tray 1 and Tray 2 Harnesses:
1. Remove the No Paper Sensor.
2. Disconnect P/J24 from HVPS/MCU.
3. Test the harnesses for continuity at
these points:
P/J245-1 <=> P/J240-3
P/J245-2 <=> P/J240-2
P/J245-3 <=> P/J240-1
P/J248-1 <=> P/J246-3
P/J248-2 <=> P/J246-2
P/J248-3 <=> P/J246-1
Are all the conductors continuous?
7 Check the HVPS/Engine Logic Board:
1. Disconnect P/J11 from the HVPS/
Engine Logic Board.
2. Test the following points for continuity:
P/J11-16 <=> P/J24-6
P/J11-16 <=> P/J24-1
Are both continuous?
8 Replace the No Paper Sensor (page 8-28,
page 8-38).
Does the problem still occur after
replacement?
General Troubleshooting
Yes
Go to step 5.
Go to step 7.
Go to step 8.
Go to "LVPS (Low
Voltage Power
Supply)" on
page 4-4.
Replace the
HVPS/Engine
Logic Board
(page 8-89).
No
Go to step 6.
Replace the
Chute Assembly
Harness.
Replace the
Tray 1 or Tray 2
Harness.
Replace the
HVPS/Engine
Logic Board
(page 8-89).
Problem solved.
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