Subject Tip Postedsort descending Image
Firmware Update Causing Poor Fusing in the HP LJ M601, M602, M603

A recent firmware update for the M601/M602/M603 has an error that resets the default Print Mode for plain paper too Light mode instead of Normal mode, and as a result causes fusing issues, namely, smeared toner, and the repetition of the image down the page (ghosting). Changing the print mode to normal mode (or to heavy mode if problems persist) is the solution. The instructions for this task are below. 

6 years 8 months Alt
Resolving the 50.3 Fuser Error in the HP P4015, P4015, and P4515

Diagnostic Tips for the 50.3 Fuser Error on the HP P4014, P4015, and P4515

On majority of HP machines the 50.3 fuser error is related to a high temperature reading in the fusing assembly, RM1-4554-000. The good thing about this particular error is that it usually is solved without replacing the fusing unit. In this article I’d like to talk about possible situations that can cause the issue and how to go about solving it.

1. Since the error is related to a high temperature reading turn the machine off and let it sit 20 to 30 minutes. One thing you don’t want to do is turn it off then back on right away. Since the fusing assembly is already overheating turning it back on right away can cause it to heat up more and permanently damage the unit.

2. Check your environment –  Make sure you have proper ventilation. I usually recommend 4 to 6 inches of clearance around all sides of the machine. Also make sure the machine is not in an extremely hot environment. This last year with it being so hot I had several customers with machines out in factories or shipping departments have overheat issues in their laser printers.

3. Media –  Running large print jobs with heavy cardstock can cause overheat issues. If you specify that you are using heavy cardstock in most modern printers the machine heats up the fuser more. So the fusing unit might normally run at around 350 decrees whereas on heavy cardstock it could run at around 375 decrees. Sometimes the fuser can’t stay at the correct temperature and it keeps rising under these circumstances. To avoid this problem break the large print job into smaller jobs with time to cool down in between jobs.

4. If all the steps above have failed to solve your 50.3 fuser error then it’s time to replace the fusing assembly.

6 years 7 months Alt
Printer Laserjet 600 M602 error 13.b9.ff Jam in top cover area

The event code: 13.B9.FF indicates that the printer believes there is a jam at the fuser output sensor, at power on. 

ALL 13.B9 errors are fuser jams related to the fuser output sensor PS700. These will be displayed as 13.B9.yz

The last set of characters will define the type of JAM the machine reported.

The First character represents the Type of Jam.

  • A = STAY (paper is still present after x amount of time)
  • D = DELAY (paper did not reach sensor in time)
  • C = WRAP (media possibly wrapped at fuser)
  • F = RESIDUAL ( Paper present at sensor during power up)

Less Likely ones but still possible

  • B = Multifeed
  • E = Door Open

The Second character defines the tray the media was printing from.

  • 1 = Tray 1
  • 2 = Tray 2
  • 3 = Tray 3
  • 4 = Tray 4

I would recommend following steps:


 Open the top cover, remove the toner cartridge, and make sure there isn't any paper in the area.

  -  Open the back cover and make sure there isn't any paper in the area.

  -  Remove the back cover and remove the fuser by squeezing the blue tabs on the fuser.  Again, make sure there isn't any paper in the fuser or in the area.


If you do not find the paper, it is possible that the fuser is faulty and you might need to have a service person look at it.



6 years 6 months
Tape the sensor flag when changing rollers

When changing the rollers in tray 2 or optional trays on the models listed below it is HIGHLY recommended to tape the sensor flag up, into the sensor, to prevent it from moving out of position. It will usually require drive assemblies to be removed for correct reinstallation that can easily add an hour or more to the repair time.



LJ1320, LJ 2300 SERIES, LJ 2400 SERIES, LJ P2015, LJ P2055, LJ P3005, LJ P3015, LJ M521, LJ M525, LJ M2727, LJ M3035

6 years 5 months
All HP formatters, DC controllers/ engine boards/ ECUs

When replacing formatter card, or DC controller (or engine board or ECU, or whatever name HP has designated for your model) there is a procedure to allow the printer to write to the replacement and save the tech the hassle of having to correct S/N, page count, etc. Unfortunately most techs do not follow the procedure and make extra work for themselves. This is due to one of 2 reasons- either they did not read the instructions in the manual or they read them and they are so poorly written they do not do the steps correctly. The correct method is very easy but HP does not write them well.

After replacing any of the parts listed (remember- never replace more than 1 at a time) do the following steps-

Remove any input or output options and removable duplexer if present.

Disconnect from the host- USB, Ethernet, phone line, etc.

Power on the printer, wait for it to come ready, wait 5 minutes.

Power off. Wait 30 seconds.

Power on the printer, wait for it to come ready, wait 5 minutes a 2nd time.


Over 90% of the time all settings will transfer over.


This is not just a convenience issue. Often the part being replaced has come from a different model and that can disable some functions, such as duplex or network capabilities, or change the speed causing timing issues.

6 years 5 months
nvisible buttons for secondary service menu

Many of the smaller HP printers have a secondary service menu. The manuals will refer to the LEFT ARROW, callout 1 below (not to be confused with the return arrow) and the CANCEL (X) button, callout 2 below. These buttons do not light up on all models and are a source of frustration for many techs. 









6 years 5 months Alt, Alt