How to Troubleshoot 13.20 Paper Jam Errors - HP LaserJet 4200, 4300, 4240, 4250 and 4350 Series Printers


A 13.20 error can occur on power up when the printer thinks paper is still stuck in the paper path. This error can occur if paper is stuck in the path holding down one of the paper path sensors. The error can also occur if one of the sensor flags is stuck in a down position.

NOTE: A sensor flag is a lever that moves as the paper passes and blocks or unblocks the actual optical sensor.

This can also be a false jam, in some cases no paper is found in the path; but the error condition is created due to a stuck sensor flag or in some cases a faulty sensor.

NOTE: At initial power on, if the printer fails to initialize the main drive assembly (main motor) focus on the fuser area of printer. If you do get main motor initialization, then focus needs to be on the top of page and pre-feed sensors.

13.20 Troubleshooting Instructions

  1. Inspect the entire paper path for a stuck piece of paper or obstruction. Sometimes paper will jam and part of the page may rip off and be left inside the printer.
  2. Locate the pre-feed sensor and look for a paper jam. Open the top cover, remove the toner cartridge, pull out the plastic block (with #4 on it), press down on the part with the #5 on it, this opens up the paper path so you can see the path that paper takes when coming from the lower trays (See Figures 1 and 2). Look down into the paper path. The flag for pre-feed sensor is off center to the left (See Figure 3). Paper will often tear off and be stuck in this area, look for small scraps of paper.

    Figure 1: Detail showing location of removable plastic piece #4 and push down plastic piece #5

    paper jam

    Figure 2: Detail showing pushing down of plastic piece #5 to aid in paper clean out and locating pre-feed sensor flag

    Paper Jam Special

    Figure 3: Detail showing location of pre-feed sensor flag

    13.20 paper jam

    3. See if the pre-feed sensor flag is moving properly. To do this, you can “floss” the paper path with a folded up sheet of paper to see if the flag moves freely. Remove tray 2. Take a piece of letter sized paper and fold it in half lengthwise twice. Push the paper up from below in between the 2 white paper guides (See Figures 4 and 5). Make sure you have removed the plastic block (with #4 on it) and are pushing down on the #5. If done correctly you can typically see the pre-feed sensor flag move when pushing paper up through the path. The thing to look for is to make sure the sensor flag is not stuck, moves freely and snaps back.

    Figure 4: Detail showing “flossing” of the paper path to see if pre-feed sensor flag is moving properly

    jammed paper hp 4200

    Figure 5: Detail showing “flossing” of the paper path. Check to see that pre-feed sensor flag is moving and snapping back in place

    paper jam hp 4300

    4. Locate the top of page sensor and see if it is moving freely. Open the top cover and remove the toner cartridge. Lift up on the green lever attached to the black metal plate. This allows us to view the paper width sensor(s) and the registration assembly (See Figure 6). Pull back on the registration plate; this is the silver metal piece with 4 black plastic knobs on it. The sensor flag for the top of page sensor is in the middle and almost directly under the registration roller. The sensor flag is difficult to see as it is directly in the middle underneath the white plastic rollers. Make sure this flag is moving and snaps back.
    5.Locate the paper width sensor and make sure it is moving freely. The flag for the paper width sensor is to the left under the same black metal plate as above (See Figure 6). Make sure this sensor flag moves freely and snaps back.(See Figure 6)

    NOTE: On the LaserJet 4240, 4250, and 4350 printers there is an additional width sensor on the right side, make sure this sensor flag is moving as well. The LaserJet 4200/4300 printers do not have a right paper width sensor.

    Figure 6: Detail showing location of top of page sensor flag, left width sensor flag, and right width sensor flag

    hp laserjet paper jam1 - Left Width Sensor 
    2 - Top of Page Sensor 
    3 - Right Width Sensor Flag  

    6. Locate the fuser sensor and check for jams or possible paper scraps stuck in the fuser. Remove the rear door; remove the fuser by grasping the blue levers and pulling back. 
    for assistance on removing the fuser. Open the back of the fuser and inspect the sensor flag in the fuser, make sure it also moves and snaps back (See Figure 7).

    Figure 7: Detail showing the location of the fuser delivery sensor flag
    hp printer paper jamCAUTION: The fuser may be hot, handle with care or let cool before handling.

    7.If a problem is found with the pre-feed sensor flag getting stuck or not snapping back, please contact your local service provider or call HP Technical Support at 1-800-HPINVENT.
    8.If the top of page sensor flag is getting stuck or not snapping back it, please contact Printer Repair Experts Technical Support at 1-888-276-4666
    9. If a problem is found with the fuser flag getting stuck or not snapping back, replace the fuser, contact Printer Repair Experts  Technical Support at 1-888-276-4666
    10. f all sensors flags seem to be moving freely and no cause can be found to attribute to the 13.20 error, please  contact Printer Repair Experts Technical Support at 1-888-276-43666