Printer Displays a Tray Empty Message

NOTE: The original Tray 4 (2000 sheet input tray) for the HP LaserJet 5SI printer is no longer available as a whole unit replacement; however parts for the tray are still available. If the entire tray needs to be replaced then it will need to be replaced with the C4781A model tray.

Parts that rarely cause the issue but may be needed.

NOTE: Do not use these parts until all troubleshooting steps are completed and replacement of the most common predicted parts fail to solve the problem.

Tray 2 empty

Verify that paper is in the tray.

Open the duplex access door.

Open and close Tray 2 and observe the tray is lifting by looking through the duplex access door.

The tray lifts, but the error is still present

Inspect the paper present flag on the PIU located just behind the pickup rollers. If standing in front of the printer, looking into Tray 2 or 3 cavities, the flag is behind the pickup roller. Ensure that it is present and not damaged.

Reload paper in tray.

Check the tray guides to ensure that they are seated correctly and are in the correct slot for the paper size in the tray.

Try another known good tray.

Replace the tray if a different tray solves the problem.

Replace the paper input unit (PIU) (see below for removal and replacement instructions).

Replace the DC controller (only after all other options) (see below for removal and replacement instructions).

Paper input unit removal and replacement

Remove Trays 2 and 3. Remove both trays to prevent damage to the PIU plastic sensor flags.

Remove front cover.

Remove the back cover.

Remove the Tray 1 pickup assembly (see below for removal and replacement instructions).

Remove the right lower door assembly.

Remove four screws (Figure 1, call-out 1).

Slide the assembly out from the chassis approximately three inches, and unplug the connector inside the right end (Figure 1, call-out 2).

Continue sliding the assembly out of the chassis.

Figure 1: Paper input unit

NOTE: Reinstall tip: Make sure Trays 2 and 3 are removed when reinstalling the paper input unit.

Tray 1 Pick up assembly removal and replacement

Remove the top cover.

Remove the front cover.

Remove the rear cover.

Remove Tray 1.

Open the pickup unit door.

Remove four screws (Figure 2, call-out 1).

Figure 2: Tray 1 Pickup unit removal

Disconnect the cables (Figure 3, call-outs 1 and 2) on the right side of the printer.

Remove the cable from the cable guide (Figure 3, call-out 3).

Figure 3: Tray 1 Pickup unit removal

Tilt the pickup assembly out of the chassis from the top (Figure 4, call-out 1), then lift up to free it from the chassis (Figure 4, call-out 2).

Figure 4: Tray 1 Pickup unit removal

Remove the pickup assembly from the chassis.

Figure 5: Tray 1 Pickup unit removal

To reinstall

First, seat the three tabs (Figure 5, call-out 1) behind the metal rail on the chassis. Then, pivot the pickup unit into place. The pickup unit has four locating pins that will engage guide holes in the chassis wen the unit is properly aligned.

DC controller PCA removal and replacement

Remove the formatter assembly.

Remove the back cover.

Remove the high voltage power supply (see below for removal and replacement instructions).

Unplug 18 connectors from the PCA (Figure 6, call-out 1).

Remove two screws (Figure 6, call-out 2) from the left side of the PCA and two self-tapping screws (Figure 6, call-out 3) from the right side of the PCA.

Release two retaining clips (Figure 6, call-out 4), and carefully tip the left side of the PCA outward to clear the formatter PCA connector from the card cage.

Figure 6: DC controller PCA

Reinstalling the DC controller PCA

Make sure the retaining clip posts (Figure 6, call-out 4) and the two locator pins (Figure 6, call-out 5) are properly aligned.

High voltage power supply (HVPS) removal and replacement

Remove the back cover.

Unplug the cable from the LVPS to the DC controller PCA (Figure 4, call-out 1), and move it out of the way.

Unplug the connector from the bottom of the HVPS (Figure 7, call-out 2).

NOTE: Do not remove the screw indicated in Figure 4, beneath the null symbol.

Remove one self-tapping screw (Figure 7, call-out 3) and two screws (Figure 4, call-out 4).

Figure 7: HVPS

Reinstall tip

Make sure that the plastic alignment pin (Figure 7, call-out 5), the connector pins, and the high voltage contacts are properly aligned before replacing the screws.

The tray does not lift and the error is still present

Remove the tray, and inspect the lifting plate in the tray for damage. Ensure that it will lift freely by hand.

Try another known good tray.

Replace the tray if a different tray solves the problem.

Replace the PIU (see above for removal and replacement instructions).

Replace the DC controller (only after all other options) (see above for removal and replacement instructions).

Replace the printer drive assembly(main gear assembly) (only after all other options) (see below for removal and replacement instructions).

Printer drive assembly (Main Gear Assembly)removal and replacement

Remove the following components in the order listed:

print cartridge

Tray 1

Tray 2

Transfer roller assembly

Front cover assembly

Back cover assembly

Tray 1 assembly

Right lower door assembly

Paper input unit (PIU)

High voltage power supply (HVPS)

Main motor

Remove two screws (Figure 8, call-out 1).

Figure 8: Main gear assembly

CAUTION: Be careful not to damage the plastic gears when removing the main gear assembly.

NOTE: A slight gentle rocking motion will help free the main gear assembly from the printer.

From inside of the PIU cavity, carefully tilt the bottom of the main gear assembly away from the chassis and down to free the gear mechanisms.

Reinstalling the main gear assembly

Observe the gear assembly position from inside the print cartridge cavity (Figure 9, call-out 2).

Figure 9: Main gear assembly

NOTE: A slight gentle rocking motion will help install the main gear assembly as it is rotated into place.

Tilt the top of the assembly inward, and insert the upper back part of the assembly in place (Figure 10, call-out 3).

Figure 10: Main Gear Assembly

Continue rotating the assembly upward into place.

Make sure that the locating pins are properly aligned and that the gear assembly fits tightly against the chassis before replacing the screws (Figure 8, call-out 4).

Tray 3 empty

Verify that paper is in the tray.

Remove Tray 2.

Open and close Tray 3 and verify that the tray lifts by watching through Tray 2 opening.

The tray lifts but the error is still present

Inspect paper present flag on the PIU located just behind the black pickup rollers. Ensure it is present and not damaged.

Reload paper in tray.

Check the tray guides to ensure they are seated correctly and in the correct slot for the paper size in the tray.

Try another known good tray.

Replace the tray if a different tray solves the problem.

Replace the paper input unit (PIU) (see above for removal and replacement instructions).

Replace the DC controller (only after all other options) (see above for removal and replacement instructions).

The tray does not lift, and the error is still present

Remove the tray, and inspect the lifting plate for damage. Ensure that it will lift freely by hand.

Try another known good tray.

Replace the tray if a different tray solves the problem.

Replace the PIU (see above for removal and replacement instructions).

Replace the DC controller (only after all other options) (see above for removal and replacement instructions).

Replace the printer drive assembly(main gear assembly) (only after all other options) (see above for removal and replacement instructions).

Tray 4 empty

Verify that there is paper in the tray.

Check for an extra ream of paper on the left side of tray. This can cause the tray to stall while lifting and result in a tray empty message.

Defeat vertical transfer unit (VTU) then close and open Tray 4 drawer and verify tray lifts.

NOTE: Follow troubleshooting steps for Trays 2 or 3 when working with the 2 x 500-sheet input tray.

The tray lifts but the error is still present

Reload paper in the tray.

Check the tray guides to ensure that they are seated correctly and are in the correct slot for the paper size in the tray.

Inspect the paper present sensor flag for correct physical operation.

NOTE: Service mode can be used to test this sensor on tray C4781A.

Replace the PIU for Tray 4 (see below for removal and replacement).

Replace the paper deck drive PCA for Tray 4 (Tray 4 main drive assembly)(only after all other options) (see below for removal and replacement instructions).

Tray 4 Pickup assembly (PIU) removal and replacement

Remove the vertical transfer unit (VTU) from the 2000-sheet Input Tray, including the two connectors that must be disconnected before removing the VTU (Figure 11, call-out 2).

Remove the right cover from the 2000-sheet Input.

Open the paper tray on the 2000-sheet Input Tray to the stops.

Disconnect the three cables located at the bottom-right side of the pickup assembly (Figure 11, call-out 3).

Remove the five screws that secure the pickup assembly to the unit?s chassis: three screws along the top, and one screw on each side (Figure 11, call-out 1).

Slide the pickup assembly straight out of the chassis.

Figure 11: Removing the PIU

Paper Deck Drive PCA (Tray 4 Main Drive Assembly) removal and replacement

Remove the back cover from the 2000-sheet input tray.

Locate the cable that runs from the main drive assembly on the 2000-sheet Input Tray to the unit?s Controller PCA. Disconnect the cable from the J206 connector on the Controller PCA (Figure 12, call-out 1).

Release the cable from the two cable clips that hold the cable to the chassis (Figure 12, call-out 2).

Remove the two screws that connect the main drive assembly to the chassis: one screw on top of the main drive assembly and one screw on the bottom (Figure 12, call-out 3).

Figure 12: 2000-sheet Input Tray Main Drive Assembly

Pull the main drive assembly away from the chassis.

Inspect the paper deck drive bushing on the main drive assembly. If the bushing is damaged, it can be replaced without replacing the whole drive assembly.

To reinstall

Re-route the cable through the cable clips (Figure 12, call-out 2) and reconnect the cable to the J206 connector on the Controller PCA (Figure 12, call-out 1).

© 2005 Hewlett-Packard