Front Panel Displays "Fatal Fault Encountered" Message; Troubleshooting - Printer Comes To A "Ready" State; False Lh Door, Rh Door, Or Front Door Open Messages; False "Load Paper In Tray [1,2,3,4]" Message - Xerox 7700DX - Phaser Color Laser Printer Service Manual

Front Panel displays "Fatal Fault Encountered" message

See procedure for "Error 81 Controller to Engine Communications Failure" on
page 2-70.

Troubleshooting - Printer Comes to a "Ready" State

False LH Door, RH Door, or Front Door Open Messages

See procedure for "Troubleshooting the Interlock Circuit", on page 3-91.

False "Load Paper in Tray [1,2,3,4]" Message

In order for the printer to recognize paper in the paper tray, one or both of the
top two Paper Size Switches must be closed, the Tray Level Sensor must be
actuated by the lift mechanism and the No Paper Sensor must be deactuated.
1. Remove the Paper Tray and check for damage. Check the No Paper
Sensor actuator for damage and freedom of movement. If it is a Universal
Tray, swap the tray with another if available.
2. If available, swap the Feeder Assembly with one from another tray. (Does
not apply to HCF Tray 4.)
3. Enter Service Diagnostics Mode and run the sensor test. Check sensor
operation by lifting and lowering the No Paper Sensor Lever while
observing the display.
4. Verify continuity of the wiring between the No Paper Sensor and the
Control Board.
5. If the problem is with Tray 2, 3 or 4, replace the Auxiliary Feeder Control
Board (RRP 1-59).
6. Replace the Engine Control Board (RRP 42, on page 7-206).

False "Tray [1,2,3,4] Missing" Message

In order for the printer to recognize the presence of a paper tray, one or both
of the top two Paper Size Switches must be closed.
Note There are special instances where a false "Tray Missing"
error can be reported. Check the fault list to ensure that
no other errors are present.
1. Check the Tray Level Sensor actuator for damage and freedom of
movement. Check the Paper Size Switches for damage.
2. Enter Service Diagnostics Mode and run the sensor test. Check the Level
Sensor operation by removing and reinserting the paper tray while
observing the display.
3. If available, swap the Feeder Assembly with one from another tray. (Does
not apply to HCF Tray 4).
4. Verify continuity of the wiring between the No Paper Sensor and the
Control Board.
5. If the problem is with Tray 2, 3 or 4, replace the Auxiliary Feeder Control
Board (RRP 60, on page 7-229).
6. Replace the Engine Control Board (RRP 42, on page 7-206).
3-94 Phaser 7700 Color Laser Printer Service Manual