Technical information

B. Print Extended Self Test:

1. Press CANCEL + OK buttons at the same time.

2. The extended self test page should print.

--- Verify all colors and all stair-step nozzles are firing (i.e. no missing horizontal lines should be

visible in the stair-step grid patterns). (NOTE: the self test page is a 'forced' test print whether the

ink cartridges are good or bad). Inspect color bars to verify proper nozzle/jetting health. If

normal/regular printing is still not permitted then the problem is with either one, or both, of the ink

cartridges. Activate Tap 41 test to confirm which cartridge is causing the issue.

C. Validate the cartridge’s electrical health by running the ‘Tap 41’ diagnostics test. Refer to video

procedure (or .pdf document) at the following links on how to activate and read the service test:

http://inkjet411.com/?page_id=544

1. Press the * and # keys simultaneously.

2. Enter 124 (or 123) at keypad.

3. Use the arrow keys to navigate to the System Menu. Select Ok.

4. Use the arrow keys to navigate to the ‘print-mech tap test’. Select Ok. Should display ‘code

= 0’.

5. Use the arrow keys to enter ‘code = 41’ (or just enter 41 on keypad). Select Ok. The Tap 41

diagnostic test pattern should begin to print.

NOTE 1: The ‘Tap 10’ (extended self test) can also be activated by pressing CANCEL + OK buttons

at the same time. Whether ink cartridges are good or not, i.e. this is a forced print test). Refer

to following 4 paragraphs (or video) on how to interpret diagnostic report.....

NOTE 2: You may also refer to this document for specific printer model ‘Tap 41’ diagnostic &

‘Cartridge Error Bypass’ step-by-step instructions: http://inkjet411.retailinkjet.com/wp-

content/uploads/2013/04/HP-74-75-Problem-Resolution_v10.pdf

--- Providing the color cartridge is partially functioning the Tap 41 diagnostic test print will be printed

(this is a forced service print test which is mainly used for the evaluation of ink cartridge electrical

health). A good HP 75/75XL color cartridge should display 600 good nozzles, while a good HP 74/74XL

black ink cartridge should show 672 good nozzles. If the results yield anything different then the ink

cartridge is likely damaged and will need to be replaced. Refer to video on how to read the printout.

---- If the printer attempts to print the diagnostic test pattern (1 page) then the printer is generally

considered operational and functional, if nothing is printed, but the printer attempts to print the

pattern, then the tri-color ink cartridge is either empty, clogged or severely electrically damaged (black