50.1 Fuser Error

A 50.1 fuser error is a fuser under temperature error. The fuser reports to the DC controller that it is not reaching the correct operating temperature. When the fuser does not come up to temperature during the warm up process, the printer will start to this error. Refer to the following sections for troubleshooting steps to isolate the issue, for instructions on printer disassembly, and for instructions on verifying successful printer repair.

Media stuck in the fuser

Remove the fuser, and examine it for media jammed around the fuser rollers. At the same time, verify that the fuser exit flag moves freely and is not damaged.

Line voltage to the printer out of specification

Turn the printer off and unplug it for 20 minutes to allow the DC controller to reset.

If the printer is plugged into a surge protector or UPS, remove it and plug the printer directly into a wall outlet.

Try a different wall outlet, one that is preferably on a different circuit.

NOTE: The above steps are important to troubleshooting this error and should be performed at all times.

Fuser incorrectly installed or defective

If you remove/replace the fuser assembly with the power ON to the printer, you can prompt a 50.1 Fuser Error.

Remove the fuser, check the connectors on the fuser and where it connects to the printer to verify there are no bent pins or pins outside their receptacles.

NOTE: HP LaserJet 8000, 8100, and 8150 printers have different fuser connections to the printer. HP LaserJet 8000 printers have two connectors (Figure 1) and HP LaserJet 8100 and 8150 printers have one (Figure 2). If either connector is cracked on an HP LaserJet 8000 printer, the assembly can be replaced separately. This connector is not available for ordering on an HP LaserJet 8100 or 8150 printer.

Figure 1: Fuser connections on an HP LaserJet 8000 printer 1-HP LaserJet 8000 fuser connectors

Figure 2: Fuser connectors on the HP LaserJet 8100 and 8150 printers 1-HP LaserJet 8100 and 8150 fuser connectors

Replace the fuser if the connectors are broken or bent. Verify that the fuser is a genuine HP fuser and not a remanufactured or third-party fuser. The fuser rollers in a genuine HP fuser will be only black.

Replace the following parts in succession of probability

Replace the fuser.

Replace the low voltage power supply.

On the HP LaserJet 8100 and 8150 printer, replace the Fuser cable 1 assembly.

Replace the DC controller board.

Disassembly steps required to replace the fuser cables
Removing several of the covers in order

Remove the control panel by lifting up firmly. Be sure to disconnect the cable.

The top cover of the printer must be removed next (three screws, one is visible after removing the control panel, another after opening the diverter access door, and the third after opening the top cover).

Remove the right-lower cover (two screws).

Remove the AC access cover in the rear of the printer by the formatter (three screws).

Remove the back cover (six screws).

Additional assemblies that need to be removed

Remove the formatter from the printer.

Unplug the formatter Fan 3 connector, then remove the fan by pinching the fan retainer clips and sliding the fan out of the printer.

Remove the formatter PCA cage (seven screws).

Remove the ground screw for the fuser cable cover.

Remove screw that holds the fuser cable cover in the printer.

Removing the fuser cable cover assembly from the printer

Carefully pull the wiring looms from the channel in the printer to get the needed slack in the cables to remove the assembly (Figure 3).

Figure 3: Removing fuser cable cover 1-Fuser cable cover

Gently pull the assembly out of the printer.

Replacing Fuser Cable 1

Carefully undo the wires from the fuser cable cover assembly.

Unclip the Fuser 2/duplex cable from the assembly.

Release both connectors from the assembly with a small, flat blade screwdriver. Lift up gently on the tab shown in Figure 4, call-out 1. Then rotate the connector in the direction shown in call-out 2. If the connector is still attached after rotating more than 45 to 60 degrees then gently pry up the tab shown in call-out 3 to release it.

Figure 4: Releasing fuser cable connectors 1-Tab to release connector 2-Rotate the connector 3-Other tab to be released

CAUTION: Be very careful releasing the connectors, or the fuser cable cover can become cracked or broken.

Follow the wires up to where they connect to the DC controller. There are two connections (Figure 5).

Figure 5: Following wires to DC controller 1-DC controller connections

Reassemble in the reverse order

Reattach the ground screw.

Reconnect the connector on the AC power supply.

Reinstall Fan 3 and its connector.