'Install Black Print Cartridge'

Control Panel Message Will Not Clear or Printer Will Not Recognize Black Print

After the black print cartridge is installed in the printer, the black cartridge lever assembly is lowered to lock it into place. This moves the black print cartridge into the developing position.

Figure 1, call-out 1 shows the location of this switch with the back cover of the printer and the Developer/Imaging Drum Bias Supply removed.

This locking action activates the black print cartridge switch (SW644) via the small rod shown in Figure 2, call-out 1. This small rod gets pushed out to engage SW644 when the black print cartridge is inserted in the printer and then moves to the bottom of the slot to engage the red micro switch shown in Figure 2, call-out 3 when the lock lever is put into the locked position. Figure 2, call-out 1 shows the position of the rod when there is no black print cartridge installed. When SW644 is activated it tells the printer the black print cartridge is installed and locked into place. Figure 3, call-out 2 shows how the rod gets pushed into position to activate SW644. If the printer is not recognizing the black print cartridge properly, this switch is the most likely cause. It may be out of position or defective.

With the printer at a READY status and the new Black Cartridge installed go into the Configuration Menu and verify that "New Black Toner" = Yes. Make sure they press SELECT to save the selection with an asterisk.

Remove the Black print cartridge and power cycle the printer.

Install the new Black Cartridge when prompted to do so by the control panel message.

If the control panel displays a message asking if the cartridge is "new", select YES.

The printer should come to a READY status. Have the customer print a Configuration Page to verify life remaining is at 100%.

Figure 1: Back cover of the printer removed1 -Location of Black print cartridge Switch (SW644)

Figure 2: Close up of properly installed Black print cartridge Switch (SW644)

1-Rod is not engaged with SW644 because no black print cartridge is installed 2-Alignment hole on SW644 (must be positioned on detent) 3-Red micro switch not activated

How to access the black print cartridge switch

To access the Black print cartridge Switch (SW644) remove the following assemblies in the order they are listed.

Remove the Left Rear Cover. This is the cover that the Formatter slides into.

Remove the Formatter.

Remove one screw, then the small rear lower left corner cover.

Remove the Top Cover assembly.

Remove the Rear Cover assembly.

Remove the sheet metal cover plate shown in Figure 4, call-out 1 (four screws).

Remove the Developer/Imaging Drum Bias supply.

Remove one screw then the Black print cartridge switch (SW644).

Figure 3: Sheet metal cover plate visible after removing top cover1 - Remove this plate

Troubleshooting steps

First, check the physical operation of the switch. To do this, install the black print cartridge and lock it into position. Watch the small rod while doing this, it should drop down and activate the small red micro switch that is part of SW644. This is where an audible click should be heard.

The correct position of the black print cartridge switch is critical in order for the switch to be correctly activated. Located behind SW644 is a detent that the alignment hole on SW644 shown in Figure 2, call-out 2 must fit onto (that ensures the correct position of the black print cartridge switch.)

If the switch is not activating properly, then loosen the screw attaching it to the printer and attempt to realign it so that the switch activates when the black print cartridge is locked into position. Make sure that SW644 is positioned on the detent properly.

If this does not resolve the issue, then replace the switch. Make sure that SW644 is positioned on the detent properly when installing it.

If a new switch does not resolve the issue, then use an OHM meter to check the cabling. SW644 is cabled directly to J644 on the Main Relay PCA. SW644 is commonly open. To check the switch functionality use a multimeter set in the OHM position and check the continuity to the switch when it is in the closed position. Continuity denotes a functional switch.

© 2005 Hewlett-Packard