51.10 Printer Error – HP Laserjet 4200, 4250, 4300, 4350 Printer
51.10 printer error  – HP Laserjet 4200, 4250, 4300, 4350 Printer
The 51.10 printer error in the HP laserjet 4200, 4240, 4250, 4300, and 4350 printer is related to the laser scanner unit. Most the time when this error happens the machine starts up and goes to a ready state. It’s not till you send a print job to the machine that the display reads the 51.10 printer error. In this article I will discuss this error message, relate ways to troubleshoot it, and tell you how to replace the laser scanner unit if needed.
Troubleshooting the 51.10 printer error  in the HP Laserjet 4200, 4300 Series Printers
Troubleshooting the 51.10 printer error is typically pretty easy as the machine will not do anything else but produce the error when a print job is sent to it. When on site go into the information menu from the control panel and tell the printer to print a configuration page. If the printer gets the error then follow the steps below. If the printer prints the config  page go to the diagnostics menu and print off the error log to verify the machine has been producing the error in the past. Anyway at this point there is not much more to do. You probably will end up replacing the laser scanner assembly for the 51.10 printer error. Follow the instructions below to replace the laser scanner assembly or to reseat the cables.
1. Press the SELECT (Check) button to continue.
2. Turn the printer off and then on.
3. Reseat  the connectors between the laser/scanner and DC controller PCA (J83  and J84).
4. Replace the laser/scanner assembly.
5. Replace the DC controller PCA.
Laser Scanner Removal
Accessory covers and the tray 2 extension door
1. Grasp the top accessory cover (the mounting position for the optional stapler/stacker or stacker). Rotate the cover toward the front of the printer to release it, and then lift it up to remove it.
Formatter cover
1. Grasp the formatter cover.
2. Pull the cover straight back and away from the printer.
Top cover
1. Remove the top accessory cover.
2. Remove the two rear mounting screws.
3. Open the print-cartridge door. Remove the front two mounting screws.
4. Use needle-nose pliers to release the print-cartridge drive-arm.
5. Open tray 1 and the rear door. Grasp the top cover and carefully rotate the left edge up and away from the printer. Do not apply stress to the control-panel wire-harness  when rotating the top cover away from the printer.
6. Disconnect the control-panel wire-harness  from the DC controller PCA. Remove the top cover
When the top cover is re-installed, make sure that the wire-harnesses are properly routed through the cable guides. If the wire-harnesses are not properly routed, they can be damaged when the top cover is installed.
Right Side Cover
1. Remove the following assemblies: Formatter cover and Top Cover.
2. Release the upper right-side cover-locking tab near the formatter.
3. Locate the arrow that is embossed on the tray-number indicator. Use a small flat-blade screwdriver to push in on the lower cover-locking tab to release it.
4. Locate the arrow  that is embossed on the pickup gear cover near the optional envelope feeder power connector. Use a small flat-blade screwdriver to push in on the locking tab to release it
5. Open the formatter door and rotate the right-side cover away from the printer and lift it up to remove it.
When you install the right-side cover, verify that the power-switch arm locks onto the switch connecting rod
Laser/scanner assembly
1. Remove the following assemblies: Top cover  and Right-side cover.
2. Unplug the laser/scanner wire-harness connector from the DC controller PCA. Remove the laser/scanner wire-harness from the wire guide.
3. Unplug the laser/scanner wire-harness from the laser/scanner PCA
4. Remove four screws. Â Do not turn the laser/scanner adjustment screw. The two front mounting screws have grounding clips that are not captive when the screws are removed. Be sure to replace these clips when the laser/scanner is installed.
5. Carefully lift the laser/scanner up and out of the printer. Make sure the wires along the bottom of the laser/scanner assembly don’t get snagged by the assembly when the assembly is removed. When the laser/scanner assembly is installed, make sure that the wire-harnesses are properly routed through the cable guides. It the wire-harnesses are not properly routed, they can be damaged when the top cover is installed.
Conclusion about the 51.10 Printer Error in the HP Laserjet 4200, 4250, 4300, and 4350 Printers
Hopefully you will never experience the 51.10 printer error in your HP printer. Some models like the original 4000 and 8000  series  the problem was very rare. However,  I’ve noticed in the last few years a lot more errors and noises coming from laser scanner units in all makes and models. I’m not sure if its related to the speed that the units now rotate at or if it’s just cutting cost and making products at a lower quality. I hope manufactures take note of the forums and articles written in regard to these 510.10 printer errors and make sure the quality of the parts they put in the machine match the companies reputations.
Find additional printer service tips, manuals, and parts diagrams at: http://www.lbrty.com/resources.html/
