Sunday 4 March 2018

HP LaserJet printer – Clearing Jams – Troubleshooting – Function check – High voltage contact check – Drum rotation check


HP LaserJet 1010 -1012 -1015 -1020
Clearing jams
To prevent damage to the printer when clearing jams, including jams in the output bin, always open the print-cartridge door and remove the print cartridge. Keep the door open and the cartridge out until the jam has been cleared. Opening the print-cartridge door and removing the print cartridge relieves tension on the printer rollers, which prevents damage to the printer and makes the removal of jammed pages easier.
Typical media jam locations
Print cartridge area: 
Input tray area: If the page is still sticking out of the input tray, gently try to remove it from the input tray without tearing the page. If you feel resistance, see  Output path: If the page is sticking out of the output bin.
Removing a jammed paper
Media jams might result in loose toner on the page. If you get any toner on your clothes, wash them in cold water. Hot water will permanently set the toner into the fabric.
To prevent damage to the printer when clearing jams, including jams in the output bin, always open the print cartridge door and remove the print cartridge.
To prevent damage to the print cartridge, minimize its exposure to direct light. Cover the print cartridge with a sheet of paper.
1. Open the print cartridge door, and remove the print cartridge.
2. Grasp the middle edge of the side of the media that is most visible, and carefully pull it free from the printer
Do not use sharp objects, such as tweezers or needle nose pliers, to remove jams. Damage caused by sharp objects will not be covered by the warranty.
Always pull jammed media in the direction it would travel through the paper path.
Do not forcefully pull jammed media against the direction of travel through the paper path to avoid damage to the printer.
3. When you have removed the jammed media, replace the print cartridge, and close the print cartridge door.
After clearing a media jam, you might need to turn the printer off then on again.
When you add new media, remove all of the media from the input tray and straighten the stack of new media.
Troubleshooting
No power is available because the power source, cable, or switch failed.
1. Verify that the product is plugged in. Make sure that the printer is plugged directly into a working wall receptacle.
2. Verify that the power cable is functional and that the power switch is on.
3. If these conditions are correct, replace the engine power assembly.
The printer motor does not rotate.
1. Make sure that the printer is plugged directly into a working wall receptacle.
2. Verify that the print-cartridge door is closed.
3. Verify that the print path is clear. If it is, verify that the print path paper-sensor arms are clean and functional.
4. Verify that the cable from the ECU to the motor is connected.
5. If these conditions are correct, replace the ECU.
6. If, after replacing the ECU, the printer motor still does not rotate, replace the engine-power assembly.
7. If, after replacing the ECU and engine-power assembly, the printer motor still does not rotate, replace the printer.
The media does not move smoothly through the paper path
If the media is consistently jamming and the paper path is clear, replace either the paper-pickup assembly or the fuser, depending on where it is jamming.
Functional checks
This section includes five functional checks for troubleshooting.
Half self-test functional check
The print process can be subdivided into the following stages:
Image-formation stage (charges the drum and writes a latent image to the drum with the laser)
Development stage (forms a toner image on the drum)
Transfer stage (transfers the image to media)
Cleaning stage (removes excess toner from the drum)
Fusing stage (applies heat and pressure to make the image permanent on the media)
To perform a half self-test check
The purpose of the half self-test check is to begin the printing process and then interrupt it in the middle. Examining the printer components at that point allows you to determine which stage in the print process is malfunctioning.
1. HP LaserJet 1010 series: Press the GO button to print a demo (self-test) page.
HP LaserJet 1020 printer: Open the Printer Properties dialog box. Select Print Test Page to print a test page. Click OK to close the HP LaserJet 1020 test page troubleshooting dialog box. Click OK again to close the Printer Properties dialog box.
2. Open the print-cartridge door the instant the leading edge of the paper exits the printer.
3. Remove the print cartridge.
4. Open the print cartridge drum shield to view the drum surface. If a dark and distinct toner image is present on the drum surface, then the first two functions of the electrophotographic process are functioning (image-formation and development). Any failure is occurring in the transfer or fusing stag.
To perform other checks
If no image appears on the photosensitive drum, perform these checks:
1. Make sure that you remove the entire length of the sealing tape from the print cartridge before you install the cartridge. If the tape is not removed, then toner cannot reach the drum.
2. Perform a drum-rotation functional check to ensure that the drum is rotating
3. Perform a high-voltage contact check.
4 Check the fuser connections (callout 1) on the engine-power assembly. Also check the high voltage connection at the back side of the printer.
The following figure shows the HP LaserJet 1010 series products. The connections are located at the same place on the HP LaserJet 1020 printer.
If a transfer problem exists, replace the transfer roller (do not touch the black-sponge portion of the transfer roller). If a fuser problem exists, first check to make sure that the four cables to the fuser are correctly seated in the engine-power assembly.
Drum-rotation functional check
The photosensitive drum, which is located in the print cartridge, must rotate in order for the print process to work. The photosensitive drum receives its drive from the main motor through a system of gears on
the right side of the printer.
1. Open the print-cartridge door.
2. Remove the print cartridge.
3. Mark the drive gear on the cartridge with a felt-tipped marker. Note the position of the mark.
4. Install the print cartridge and close the print-cartridge door. The startup sequence should rotate the drum enough to move the mark.
5. Open the print-cartridge door and inspect the gear that was marked in step 3. Verify that the mark moved.
If the mark did not move, inspect the drive shaft that moves into the print-cartridge area when the printcartridge door is closed to make sure that it is meshing with the print cartridge. If the drive shaft looks functional and the drum does not move, replace the print cartridge. If the drive shaft is damaged, replace the printer.
High-voltage-contacts check
The high-voltage contacts in the printer must have a good connection with the contacts on the print cartridge to provide the necessary voltages for the electrophotographic processes. To check the print-cartridge contacts.
Remove the print cartridge and visually inspect the three connection points (callout 1) on the end of the print cartridge. If they are dirty or corroded, clean the connection. If they are damaged, replace the print cartridge.
Use a dry cloth to clean the connections
To check the printer high-voltage contacts. 
The printer has three spring-loaded pins (callout 1) that make contact with the high-voltage points on the print cartridge. Verify that the pins are not dirty or corroded and that the spring-loading action is functional. If the pins are dirty or obstructed, clean them. If they are damaged, replace the printer.
Solenoid, sensors, switches, and motor location
The following figure shows the locations of the solenoid, sensors, and switches.
1. The door switch detects whether or not the print-cartridge door is closed. Printing cannot continue until the print-cartridge door is closed.
2. Power switch
3. The paper-width sensor senses the width of the media.
4. The paper-delivery sensor senses when media has successfully moved out of the fusing area.
5. The top-of-page sensor detects the leading and trailing edges of the media. It synchronizes the photosensitive drum and the top of the media.
6. Solenoid
7. Motor

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