Individual component diagnostics

LED diagnostics
LEDs on the formatter can help identify and troubleshoot product problems.

LED indicators
Three LEDs on the formatter indicate that the product is functioning correctly.


Figure 3-1 Formatter LEDs

Hp laserjet service center


Formatter heartbeat LED
The heartbeat LED indicates that the formatter is functioning correctly. While the product is initializing after you turn it on, the LED blinks rapidly, and then turns off. When the product has finished the
initialization sequence, the heartbeat LED pulses on and off.

The heartbeat LED performs the following sequences:
1. The LED blinks when the product power is on.
2. If the light is not blinking, check the following:
◦ Reseat the formatter connectors.
◦ Replace the memory.
◦ Replace the formatter.
3. If the control panel display does not illuminate, perform an engine test to check the engine (see Engine-test button). You must have paper loaded in Tray 2 for the engine test.

HP Jetdirect LEDs
The embedded HP Jetdirect print server has two LEDs. The yellow LED indicates network activity, and the green LED indicates the link status. A blinking yellow LED indicates network traffic. If the green LED 
is off, a link has failed. For link failures, check the network cable connections.

For nonlink errors, print a configuration page. The second page is the HP Jetdirect configuration page.

Examine this page for any inconsistencies among the network settings.

Engine diagnostics
Printing test pages helps you determine whether or not the product engine and the formatter are functioning.

NOTE: Information pages also can be used to solve product issues. For information about printing information pages, see the product user guide.

Engine-test button
To verify that the product engine is functioning, print an engine-test page.

Print the engine test pages
NOTE: A damaged formatter might interfere with the engine test. If the engine test page does not print,  try removing the formatter and performing the engine test again. If the engine test is then successful,
the problem is in the formatter, the control panel, or the cable that connects them together. 

1. Remove the DIMM cover. See DIMM cover and DIMM on page 57.
2. Press the engine test-page button (callout 1).

Figure 3-2 Locating the engine-test-page switch
engine test button hp lj P315

The test page should have a series of horizontal lines. The test page prints from the last tray that the product used to print, unless the product has been turned off and then turned on again since the most
recent print job. If the product has been turned off and then on again since the most recent print job, then the page will print from Tray 2. The product continuously prints test pages as long as the test-page
switch is depressed. The product will not print a test page if it is in Sleep mode.

Print formatter test pages

If the engine test was successful with the formatter removed, reinstall the formatter and then print a configuration page to test the functionality of the formatter.
1. Press the Menu button .
2. Press the down arrow button or the up arrow button to navigate to the INFORMATION menu.
3. Press the OK button to select the menu.
4. Press the down arrow button or the up arrow button to navigate to the PRINT CONFIGURATION option.
5. Press the OK button to select the option and print the page.

Fuser test page
This test helps to determine if the fuser needs to be replaced, or if it has exceeded its expected life.

A customer can complete the steps below and describe the results to the Printer Repair Experts Support Technician. If the page shows no problems, the fuser does not need replacing.

Replace the fuser (see Fuser on page 100) if the page shows the following problems:
● Fuser offset repeats in the boxes on the page
● Lines or streaks on the page (usually down the edges of the page) indicate fuser contamination
1. Press the Menu button .
2. Press the down arrow button or the up arrow button to navigate to the DIAGNOSTICS menu,
and then press the OK button.
3. Press the down arrow button or the up arrow button to navigate to the PRINT FUSER TEST
PAGE menu, and then press the OK button.

Product resets

Restore factory settings
1. Press the Menu button .
2. Open each of the following menus. Press the down arrow button to highlight it and then press the OK button to select it.
a. CONFIGURE DEVICE
b. RESETS
c. RESTORE FACTORY SETTINGS

Hard disk initialization
A hard disk initialization will erase and reformat the product's hard disk. Perform hard disk initialization only if an error code displays on the control panel indicating a disk error. Always try initializing the hard
disk before replacing it.
1. Turn the product on.
2. As the product performs its power-on sequence, press and hold the Menu button until all three lights on the control panel are lit.
3. Press the back arrow . The message INITIALIZE DISC displays on the control panel.
4. Press the OK button. The product initializes the hard disk and continues the power-on sequence.

Skip disk-load
When the power is turned on the product begins the power-on sequence. By performing a power-on bypass, you can cause the product to resume the power-on sequence but not to recognize any installed
EIO hard disk. This can be helpful in isolating EIO hard-disk errors.
1. Turn the product off.
2. Turn the product on. When the memory count begins, press and hold the button. Continue holding down the button until all three product control-panel lights flash once and then remain on. This might take up to 10 seconds.
3. Press the button, and then press the Menu button .
4. Press the button or the button until SKIP DISK LOAD is highlighted.
5. Press the OK button. The product continues the power-on sequence but ignores an installed EIO hard disk.

NVRAM initialization
CAUTION: Initializing NVRAM resets 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 also need to reconfigure any computers that print to this product to recognize the product. Initialize NVRAM only when absolutely necessary. In most situations, use a cold reset to reset product variables but still retain the needed values in the SERVICE menu. 

NOTE: Before performing a NVRAM initialization, print a menu map and a configuration page. Use the information on the configuration page to reset any customer-set product configuration values that the NVRAM initialization procedure changes. Take special not of the page count, service ID, and the serial number.

1. Turn the product off.
2. Remove any installed accessories.
3. Turn the product on. When the memory count begins, press and hold the down arrow button until
all three product control-panel lights flash once and then remain on. This might take up to 10 seconds.
4. Press the up arrow button.
5. Press the Menu button . The message SKIP DISK LOAD displays on the control panel.
6. Press the up arrow button until NVRAM INIT is highlighted.
7. press OK. The product initializes NVRAM and then continues its power-on sequence.

Service ID
Use this item to show the date that the product was first used on the control panel. This eliminates the need for users to keep paper receipts for proof of warranty.
Because the product does not have an internal clock, the availability of the service ID date depends on the product being connected to a source that can provide the date, in this case a time server on the
same network as the product. When the product is not connected to a date source, the service ID is not available, and 00000 appears on the configuration page.


Product cold reset
A cold reset unlocks menus that have been previously locked and sets all control panel menu items (including EIO settings) back to the factory defaults. 

NOTE: Before performing a cold reset, print a menu map and a configuration page. Use the information on the configuration page to reset any customer-set product configuration values that the cold reset procedure changes.

1. Turn the product off.
2. Turn the product on. When the memory count begins, press and hold the OK button. Continue holding down the OK button until all three product control-panel lights flash once and then remain on. This might take up to 10 seconds.
3. After the message SELECT LANGUAGE appears on the display, press the button or the button until COLD RESET is highlighted.
4. Press the OK button. The product performs a cold reset and then continues its power-on sequence.
5. Check all I/O settings and reset any customer-set product configuration values.


Print printers configuration page
1. Press the Menu button .
2. Press the down arrow to highlight the INFORMATION menu, and then press the OK button.
3. Press the down arrow to highlight the PRINT CONFIGURATION option, and then press the OK button to print.