SERVICE LEVEL DIAGNOSTICS | RESETS HP COLOR LASERJET 5500 AND 5550

Thhis section describes the procedures to be used to perform diagnostics.

  LED diagnostics

Use the following procedure to help identify the cause of high-level printer problems. These problems are indicated by abnormalities in the printer's power-on sequence. The LED that the procedure refers to is on the formatter. This is a “heartbeat” LED that blinks on and off when the formatter is operating correctly. Use Figure 7-20. Formatter LED (shown is HP Color LaserJet 5500 model) and Figure 7-21. Formatter LED (shown is HP Color
LaserJet 5550 model) to locate the formatter LED.

1. Does the LED blink with four fast bursts at power on? If not, then perform the following
checks.
● Check the firmware.
● Check the memory.
● Check the formatter.
2. Does the LED blink at a fast, steady rate during memory testing (one blink per 8 MB)? If not, then perform the following checks.
● Check the control panel display for an error code.
● Check the memory.
● Check the formatter.
3. Is the LED off for about eight seconds, while the boot code is decompressing, before the display turns on? If not, then perform the following checks.
● Check the firmware.
● Check the control panel display for correct connections and operation.
● Check the control panel display for an error code.
4. Does the LED blink at a steady rate of one blink per second? If not, then perform the following checks.
● Check the firmware.
● Check the formatter.
● Check the control panel display for an error code.
5. If the control panel display does not illuminate, perform an engine test to check the engine. You must have paper loaded in Tray 2 for the engine test.
Figure 7-20. Formatter LED (shown is HP Color LaserJet 5500 model)

Diagnostics from the control panel

The following sections explain in more detail how to operate the various diagnostics properly.

Print the event log page
The event log lists printer events, including jams, service errors, and other printer conditions.
1. Press <Check Mark>  (HP Color LaserJet 5500) or MENU (HP Color LaserJet 5550) to open the MENUS.
2. Press <Down Arrow> to highlight DIAGNOSTICS.
3. Press <Check Mark>  to select DIAGNOSTICS.
4. Press Down Arrow> to highlight PRINT EVENT LOG.
5. Press <Check Mark>  to select PRINT EVENT LOG.
The message Printing... EVENT LOG appears on the control panel display until the printer  finishes printing the event log. The printer returns to the Ready state after printing the event log.

View the event log on the control panel display
The show event log lists the last 50 printer events on the control panel display. (The most recent event is listed first).
1. Press <Check Mark>  (HP Color LaserJet 5500) or MENU (HP Color LaserJet 550) to open the MENUS.
2. Press <Down Arrow>  to highlight DIAGNOSTICS.
3. Press <Check Mark>  to select DIAGNOSTICS.
4. Press <Down Arrow> to highlight SHOW EVENT LOG.
5. Press <Check Mark>  to select SHOW EVENT LOG.

  PQ troubleshooting
This item prints a series of print quality assessment pages that help troubleshoot print quality problems.
1. Press <check Mark> (HP Color LaserJet 5500 models) or MENU (HP Color LaserJet 5550 models) to open the MENUS.
2. Press <Down Arrow>  to highlight DIAGNOSTICS.
3. Press <Check Mark>  to select DIAGNOSTICS.
4. Press <Down Arrow>  to highlight PQ TROUBLESHOOTING.
5. Press <Check Mark>  to select PQ TROUBLESHOOTING.

Disable cartridge check (special mode test)
This diagnostic test allows you to print internal pages or send an external job to the printer with one or more print cartridges removed or swapped. Because the cartridges are not keyed, the diagnostic test can be run with one to four cartridges removed or swapped to another location. Consumable supply errors are ignored while in this mode. Once in this mode, you can navigate the menus and print internal pages or send an external print job to the printer. This diagnostic test can be used to isolate print quality problems related to individual cartridges and to isolate individual cartridge problems such as noise.

NOTE Do not remove or swap cartridges before entering the disable cartridge check diagnostic.  After entering the test, you can remove or swap cartridges.

While performing the disable cartridge check, you can navigate the menus and print internal pages as desired from the control panel. Use the button to access the menus as you normally would. You can also send external print jobs to the printer. 

To exit this diagnostic, press the CANCEL JOB (HP Color LaserJet 5500 models) or STOP (HP Color LaserJet 5550 models) button and then select EXIT DIAGNOSTICS.

Paper path sensors (HP Color LaserJet 5550 models)
This special mode test allows you to test the printer's sensors for proper operation. Each sensor is represented by a letter. A one below the letter on the display indicated paper is present. This test allows you to print internal pages or send an external job to the printer.

Manual sensor test (HP Color LaserJet 5550 models)
This test allows you to manually test paper path sensors and the door-open switch. Each sensor is represented by a letter.  

Paper path sensor test (HP Color LaserJet 5550 models)
This test displays the status of each paper path sensor.
1. Press MENU to open the MENUS.
2. Press <Down Arrow>  to highlight DIAGNOSTICS.
3. Press <Check Mark> to select DIAGNOSTICS.
4. Press <Down Arrow> to highlight PAPER PATH TEST.
5. Press <Check Mark>  to select PAPER PATH TEST.
6. The printer displays a message similar to:
        ABCDEF....
        010010....

NOTE The number of alpha and numeric characters varies according to the number of input paper sheet feeders that are installed.

7. To exit, press STOP.
8. The printer displays the message NO JOB TO CANCEL, and enters the ready dignostics
mode. To exit, press STOP.
9. The printer displays the message DIAGNOSTICS. Press to highlight EXIT DIAGNOSTICS.
10. Press <check mark>  to select EXIT DIAGNOSTICS.
11. The printer displays the message WAITING FOR PRINTER TO RE-INITIALIZE.
The printer will return to the Ready state once initialization is complete.

Paper path test (HP Color LaserJet 5500 models)
This diagnostic test generates one or more test pages that you can use to isolate the cause of jams.

To isolate a problem, you can specify which input tray to use, specify whether to use the duplex path, and specify the number of copies to print. Multiple copies can be printed to help isolate intermittent problems. The following options become available after you start the diagnostic feature:

● Print test page. Run the paper path test from the default settings: Tray 2, no duplex, and one copy. To specify other settings, scroll down the menu     and select the setting, and then scroll back up and select PRINT     TEST PAGE to start the test.
● Source. Select Tray 1 or Tray 2. Trays 3, 4, or 5 (HP Color LaserJet 5550 models only) are optional.
● Duplex. Enable or disable 2-sided printing.
● Copies. Set the numbers of copies to be printed; the choices are 1,10, 50, 100, or 500.

1. Press  <Check Mark>  (HP Color LaserJet 5500 models) or MENU (HP Color LaserJet 5550 models) to open the MENUS.
2. Press <Down Arrow>  to highlight DIAGNOSTICS.
3. Press <Check Mark> to select DIAGNOSTICS.
4. Press <Down Arrow>  to highlight PAPER PATH TEST.
5. Press <Check Mark>  to select PAPER PATH TEST.
6. Select the paper path test options when the printer prompts you. ,

  Engine resets

Cold reset 
A cold reset unlocks menus that have been locked and resets variables in the control panel.  However, it does not clear the values in the Service menu (such as the serial number and page counts).

To perform a cold reset
1. Turn the printer on.
2. As the printer performs its power-on sequence, press and hold until all three lights on the control panel are lit.
3. When Select A Language appears on the display, press until COLD RESET appears on the display. 
4. Press .<Check Mark>  The printer will perform a cold reset and then continue its power-on sequence.

NVRAM initialization

CAUTION Initializing NVRAM will reset the serial number, the event log, the page counts, the calibration settings, and the EIO card. Use the Service menu to restore the serial number and page counts. You will also need to reconfigure any computers that print to this printer to recognize the printer. Initialize NVRAM only when absolutely necessary. In most situations, use a Cold reset to reset printer variables but still retain the needed values in the Service menu.

Before initializing NVRAM, print a configuration page and a supplies status page to gather the following information:
● Total page count and color page count
● Transfer kit count
● Fuser kit count
● Serial number

To initialize NVRAM
1. Turn the printer on and watch the control panel display.
2. When the display begins showing the memory count, press and hold until all three lights on the control panel are lit.
3. Press .<Up Arrow> 
4. Press PAUSE/RESUME for the HP Color LaserJet 5500 or press STOP for the HP Color LaserJet 5550. The display should show SKIP DISK LOAD.
5. Press <Up Arrow>  until NVRAM INIT is highlighted.
6. Press . <Check Mark> The printer will initialize NVRAM and then continue its power-on sequence.

NOTE An NVRAM INIT will not always correct all CPR problems. NVRAM INIT only erases calibration values from NVRAM in the formatters. If you have done a full calibration and still have CPR issues, you should clear the NVRAM in the DC Controller. Currently, there is no feature available in the control panel to reset calibration values for both formatter and DC Controller. To perform the reset, open the top cover and press the Engine Test button for a few seconds. When you close the cover, the control panel display will indicate that the printer is performing a calibration. The calibration values are being cleared from the Controller NVRAM. This procedure might also be required to recover CPR.

Hard disk initialization
A hard disk initialization will erase and reformat the printer’s hard disk. Perform hard disk initialization only if an error code appears on the control panel indicating an EIO disk error.  Always try initializing the hard disk before replacing it.

To initialize the hard disk
1. Turn the printer on.
2. When the Memory Count appears on the display, press and hold the MENU button.
3. When the LED's are all on and steady, release the MENU button.
4. Press and release the button. You should now see INITIALIZE DISKS on the control panel.
5. Press and release the button.

Calibration bypass
During certain diagnostic procedures, you will need to bypass the automatic calibration that is performed whenever the printer is turned on.
To bypass calibration
1. Turn the printer on and watch the control panel display.
2. When the display begins showing the memory count, press and hold until all three lights on the control panel are lit.
3. Press .<Up Arrow>
4. Press PAUSE/RESUME. The display should show SKIP DISK LOAD.
5. Press <UP Arrow>  until SKIP CALIBRATION is highlighted.
6. Press <Check Mark> The printer will skip calibration and then continue its power-on sequence.

Calibrate now (HP Color LaserJet 5500 models only)
Use the following procedure to calibrate the printer whenever you replace the DC controller, the ETB, the drum drive motors, the drum drive gears, or a laser/scanner.
1. Press <Check Mark>  to enter the MENUS.
2. Press <Down Arrow> to highlight CONFIGURE DEVICE.
3. Press <Check Mark>  to select CONFIGURE DEVICE.
4. Press <Down Arrow> to highlight PRINT QUALITY.
5. Press (Check mark>  to select PRINT QUALITY.
6. Press <Down Arrow> to highlight CALIBRATE NOW.
7. Press <Check mark> to select CALIBRATE NOW.
8. Wait for the printer to calibrate.

Full calibrate now (HP Color LaserJet 5550 models)
Use the following procedure to calibrate the printer whenever you replace the DC controller, the ETB, the drum drive motors, the drum drive gears, or a laser/scanner. Full Calibrate Now includes the Quick Calibrate routines and adds Drum Phase Calibration and Color Plane Registration. Full Calibrate lasts for about 3 minutes and 15 seconds.
1. Press MENU to open the MENUS.
2. Press <Cown Arrow>  to highlight CONFIGURE DEVICE.
3. Press <Check mark>  to select CONFIGURE DEVICE.
4. Press <Down Arrow>  to highlight PRINT QUALITY.
5. Press <Check mark>  to select PRINT QUALITY.
6. Press <Arrow Down> to highlight FULL CALIBRATE NOW.
7. Press <Check mark>  to select FULL CALIBRATE NOW. Wait for the printer to calibrate.

NOTE Full Calibration only clears the DC Controller values. It does not clear values in the formatter. To clear values in the formatter, open the top cover and press the Engine Test button (located at the side of the printer as shown in Figure 7-27) down for several seconds.