Ресетиране на нивото на мастилото при мастилници HP 51641, HP 51645, C1823, C6615, C6578 (на английски)
If you currently use the following HP ink jet cartridges
HP 51641, HP 51645, C1823, C6615, C6578
this will allow you to reset the ID system & Ink Level Indicator built into the printer.

RESETTING
Remove cartridges from your printer.

Place a piece of scotch tape over the top left four contacts as shown in the picture to the right.

Place cartridge(s) back into printer, close lid and wait 10 seconds. The tape needs to be on the contact points when inserting cartridges.

Lift the lid and wait for cartridge to return to "changing area". The printer may show an error message at this time. This is not uncommon and is nothing to be concerned about.



Remove cartridge from printer.

Remove tape from left contact point and place on top right four contact points as shown in the bottom image.

Place cartridge(s) back into printer, close lid and wait 10 seconds. The tape needs to be on the contact points when inserting cartridges.

Lift the lid and wait for cartridge to return to "changing area". The printer may show an error message at this time. This is not uncommon and is nothing to be concerned about.

Remove cartridges from printer.

Remove tape from cartridges.

Place cartridge back into printer. Cartridge ink level indicator should now read full.

Additional Notes:
In some cases this process does not fully work.
If for some reason your printer is being stubborn the you will need to repeat the entire process above, with the top three contact and then repeat one more time covering the top two.