The chip on your cartridge what it stores, why a compatible cartridge needs one, and the point where a check turns into a block
Look at the end of an ink cartridge and you will find a row of gold contacts on a small plastic plate. That is the chip, and almost every argument about printer ink comes back to it. The level warning that fires early is the chip. So is the compatible cartridge that worked for a year and then stopped, and so is the reason a remanufactured cartridge behaves differently from a brand new third party one. It helps to know what the thing is doing before you decide who to blame.
What is physically on the plate
The chip is a small integrated circuit with a handful of exposed contacts. When you push the cartridge home, spring pins in the carriage meet those contacts and the printer can read from and write to a few kilobytes of memory. That is the whole physical story. There is no sensor looking at the ink, no float, no window.
What lives in that memory is a short record of the cartridge: which model it is, which colour, which yield class, a serial number, a manufacturing date, and a running count of how much has been used. On newer cartridges there is also a cryptographic identity. HP says that Original HP office printer cartridges introduced since 2015 use smart card technology that allows a secure transaction between the printer and cartridge, and describes those chips as using the secure smart card technology commonly found on chip-based credit and debit cards.
Two things people often merge are worth keeping apart. The chip is not the print head. On an HP or Canon inkjet the print head is frequently built into the cartridge as well, which is a much larger and more expensive component, and a fault in it produces banding and missing colours rather than a rejection message. Our guide to reading a nozzle check covers that side. The chip only carries information. The head is the part that puts ink on paper.
Toner cartridges carry the same arrangement, and so do drum units on the lasers that meter a drum separately. Of the 257 printers in our catalogue, 154 take ink cartridges, 79 take toner and 24 are bottle-fed tank machines where the ink arrives in a plain bottle with no chip at all.
Your ink level is a counter, not a measurement
The printer does not know how much ink is in the cartridge. It knows how many drops it has fired, and it subtracts them from the rated yield stored on the chip. The gauge on your screen is arithmetic.
You can prove it from the manufacturers' own instructions. Canon publishes a procedure for clearing support code 1731 by holding the Stop button for at least five seconds, which disables the remaining ink level detection function and lets the machine keep printing. A printer with a real sensor would have nothing there to disable.
Several familiar complaints follow straight from that:
- A refilled cartridge still reads empty. You put ink in, but nobody reset the number. The count carries on from where it stopped.
- The warning arrives before the ink runs out. The rated yield is a conservative average measured under a test standard, not a promise about your pages. What page yield really measures explains why your mileage differs, and what the low ink gauge really means covers printing past it on each brand.
- A cartridge with no readable chip shows no level at all. Epson notes that with non-Epson cartridges installed the ink cartridge status may not be displayed. The ink is there. The bookkeeping is not.
None of that is the lock. A machine can lose track of the level and still print perfectly well, which is exactly what happens after you override the detection.
Three jobs, and only the third one stops you printing
Every argument about cartridge chips gets clearer if you separate what the chip is being asked to do at any moment.
| Job | What the printer is asking | What goes wrong | Does it stop you printing |
|---|---|---|---|
| Identify | Which cartridge is this, what colour, what yield class, is it meant for this machine | Wrong region or wrong model fitted, dirty or bent contacts | Yes, but the fix is mechanical |
| Meter | How much of the rated yield is left on the counter | Reads empty when full, reads nothing at all | Only until you override it |
| Authenticate | Can this chip complete the maker's cryptographic handshake | The chip is not the maker's, or is a clone the current firmware rejects | Yes, and no override exists |
Identify and meter are housekeeping. Every brand does both, and neither is controversial. The third row is the one that produces news stories, and it is not universal. Across the 257 machines we track, 84 carry a documented firmware policy that can refuse a cartridge on authentication grounds, which is 33 percent of the catalogue. Of those, 60 are HP and 24 are Epson cartridge models. The remaining 173, covering every Brother and Canon machine on the site along with 45 HP models and all 22 Epson EcoTanks, meter and identify without an authentication gate that can shut the machine down.
The HP side splits across both supply types: 39 inkjets and 16 laser machines. Toner being affected surprises people, because Dynamic Security was reported as an inkjet story for years. Our firmware DRM tracker lists every model with the notice HP publishes for it, and the four brand pages cover each maker's stated position: HP, Brother, Canon and Epson.
Epson sits slightly apart from the other two open brands. It warns rather than blocks, but it does state that firmware updates may affect the functionality of third-party ink, and that non-Epson branded or altered Epson cartridges that functioned prior to a firmware update may not continue to function. That is a real caveat, not a lock in the HP sense.
Why a remanufactured cartridge survives an update and a new compatible one does not
People notice this pattern without usually being given a reason for it. Two third party cartridges, same price bracket, same shop, and after a firmware update one keeps working and the other is refused. The difference is where the chip came from.
A remanufactured cartridge is a used original that has been stripped, cleaned, refilled and tested. It carries the maker's own chip, the one that came off the production line. A new-build compatible cartridge is a fresh moulding that has never been inside a printer, so it needs a chip made by somebody else, designed to answer the printer's questions the way the original would.
HP is unusually direct about what that means. It says its dynamic security measures block cartridges using non-HP chips or modified or non-HP electronic circuitry, and that reused, remanufactured and refilled cartridges that reuse the HP chip or electronic circuitry are unaffected. That is a buying instruction written into a policy document. On an HP machine with the notice attached, the reused chip is the safe path.
It also explains the trade in empty cartridges. Remanufacturers need intact used shells with working chips, which is why they will pay for your empties and why they will not pay for one that has already been through the process. What to do with empty cartridges covers that side, and OEM versus compatible versus remanufactured prices the three routes out against each other.
The catch is that a clone chip is not automatically worse. On the 202 machines with no authentication gate, a well-made compatible cartridge and a remanufactured one are competing on ink quality and build, and the chip is a non-issue. The reused chip only buys you something specific: immunity from a lock that most printers do not have. Judging a third party cartridge covers the things that do matter on an open machine.
Reading the error: chip fault or authentication block
The message on the panel tells you which of the three jobs failed, if you know what to listen for. The distinction that matters is whether the printer is saying it cannot read the chip, or saying it read the chip and did not like the answer. The first is usually fixable in two minutes with a dry cloth. The second is not fixable at all.
| What you see | Which job failed | What it usually means |
|---|---|---|
| Cartridge problem, incompatible, incorrect, missing or damaged | Identify | Contacts, seating or a genuinely wrong part. Power the machine off at the wall, wait, reseat the cartridge and wipe the contacts before assuming anything worse |
| Epson: cannot recognize ink cartridge, check that the ink cartridges are installed correctly | Identify | Epson is telling you it could not complete the read. Reseat first |
| Ink level unknown, or no gauge shown for one slot | Meter | The chip is readable but the counter is not usable. Epson notes the status may not be displayed with non-Epson cartridges. The printer will still print |
| Canon support code 1731, or a warning that remaining ink cannot be determined | Meter | Canon publishes the override: hold Stop for at least five seconds to disable remaining ink level detection |
| Epson: non-genuine cartridge, other brands may not function properly | Meter, with a warning attached | A prompt, not a block. Epson recommends declining, and you can usually continue |
| HP: cartridge from a non-HP chip or modified circuitry, or a cartridge that worked yesterday now refused | Authenticate | This is the firmware block. Reseating will not help and a second cartridge of the same make will fail the same way |
The tell for the third case is timing. An authentication block arrives without you having touched the hardware, often after an overnight update, and it hits every cartridge from that supplier rather than the one you just fitted. A contact problem arrives the moment you change a cartridge and moves when you swap the cartridge between slots.
For the step by step version of the first two rows, fixing an HP cartridge not recognized error and clearing an Epson ink error walk through the resets in order. For the third row, what to do when an update rejects your ink covers the options that remain, and declining the update safely covers avoiding it next time.
Chip resetters and chipless firmware
Two products exist to get around chips. They get confused with each other constantly, and they solve different rows of the table above.
A chip resetter is a small battery powered cradle you press the cartridge against. It rewrites the counter to full. That is all it does, and it does it to the metering job only. So a resetter is the right tool for a cartridge you refilled that still reads empty, and it is the wrong tool for a cartridge the printer refuses to authenticate. If your problem is the bottom row, resetting the counter changes nothing, because the machine never got as far as the counter.
Resetters are also model-specific and generation-specific, and cartridge makers change chip families regularly. A resetter bought for one series will not necessarily work on the next.
Chipless firmware is a different scale of intervention: replacement firmware flashed onto the printer so it stops requiring chip data at all. It genuinely removes the problem, and it brings four costs that the sellers tend to list in small print.
- You lose ink monitoring completely. The machine no longer reads the chip, so it cannot warn you about anything. Running a cartridge print head dry is a real way to damage it, which is the failure our clogged print head guide is about.
- It is treated as one-way. Going back to stock firmware is not a supported operation and is often not possible at all.
- An interrupted flash can leave you with nothing. A firmware write that stops halfway can put the machine into a recovery state or kill it outright.
- The warranty goes. Modified firmware is not something any manufacturer supports.
Weigh that against the machine. On a printer worth less than a couple of sets of cartridges, the comparison worth making is between modifying it at all and replacing it with something that has no lock on it, which is what the cost per page ranking and the tank versus cartridge comparison are for. A bottle-fed tank machine has no cartridge chip to fight, which is a large part of why people who have had one lock out end up buying one.
The security argument, weighed fairly
Manufacturers defend cartridge authentication on two grounds: counterfeits and security. The first is straightforward and worth taking seriously. Counterfeit cartridges are a genuine trade, they are sold as originals rather than as compatibles, and a chip that proves provenance is a reasonable way to spot one. HP states that Original HP office cartridges are certified with the ISO/IEC 20243 standard for product integrity to mitigate malicious tampering and counterfeit in the supply chain.
The second ground is the contested one. HP says its chips contain tamper-resistant, proprietary HP firmware which helps prevent modification by third parties after production and helps reduce the risk of malicious code entering the cartridge chip. In January 2024 HP's chief executive Enrique Lores put it far more strongly to CNBC, saying that you can embed viruses in the cartridges, and through the cartridge go to the printer, and from the printer go to the network.
Security researchers asked about that claim were not persuaded. Ars Technica put it to several experts, who described the scenario as one that would realistically require a nation state mounting a tailored attack on a specific target, and as implausible even in a laboratory. There is no record of an attack of this kind against ordinary users.
So the chip is a real anti-counterfeiting mechanism, and the malware framing has had a much better run in press interviews than it has in threat models. Both of those can be true at once. For a buying decision the question is narrower: on the 55 machines we track with a firmware policy attached, a non-original chip is a risk to your printing whatever the reasoning behind it, and on the other 173 it is not.
Common questions
What does the chip on an ink cartridge actually do?
Three things. It identifies the cartridge, telling the printer which model, colour and yield class has been fitted. It meters usage, holding a counter that the printer decrements as it fires ink, which is where your ink level display comes from. On newer cartridges it also authenticates, proving to the printer that it is the maker's own chip. HP says cartridges introduced since 2015 use smart card technology of the kind found on chip-based payment cards for that last job. Only the authentication step can refuse to let you print.
Does the chip measure how much ink is left?
No. There is no ink sensor. The chip stores a rated yield and the printer subtracts the drops it has fired, so the level on screen is arithmetic rather than a measurement. The clearest proof is that Canon publishes a way to switch it off: holding the Stop button for at least five seconds on a support code 1731 disables the remaining ink level detection function and the machine keeps printing. This is also why a cartridge you refilled yourself still reads empty, because nobody reset the number.
Why does my refilled cartridge still say empty?
Because the counter on the chip carries on from where it stopped. Adding ink does not touch it. Your options are to override the level warning, which every brand allows in some form, or to use a chip resetter that rewrites the counter to full. Neither will help if the printer is refusing the cartridge on authentication grounds rather than complaining about the level, since in that case it never reaches the counter at all.
Will a chip resetter fix a cartridge not recognized error?
Usually not. A resetter rewrites the usage counter, so it addresses a cartridge that reads empty when it is not. A not recognized error is normally either a read failure, which is a contacts and seating problem you fix with a reseat and a wipe, or an authentication refusal, which no resetter touches. Work out which one you have first: a contacts fault appears the moment you change a cartridge, while an authentication block appears on its own after a firmware update and rejects every cartridge from that supplier.
Do remanufactured cartridges have the original chip?
Yes, that is what makes them remanufactured rather than compatible. The shell is a used original that has been cleaned, refilled and tested, and it carries the chip it was built with. HP states that reused, remanufactured and refilled cartridges that reuse the HP chip or electronic circuitry are unaffected by dynamic security, while cartridges using non-HP chips or modified circuitry are blocked. On an HP machine with that notice attached, the reused chip is the safer purchase.
Is chipless firmware safe to install?
It works, and it carries four costs worth knowing before you start. The printer stops reading chips entirely, so you lose all ink monitoring and can run a print head dry without warning. Going back to stock firmware is treated as a one-way trip. An interrupted flash can leave the machine in a recovery state or dead. And the warranty is gone. On a cheap printer, replacing the machine with one that has no authentication gate is usually the better trade.
Which printers have a cartridge chip that can lock them?
In our catalogue of 257 machines, 84 carry a documented firmware policy that can refuse a cartridge on authentication grounds. 60 are HP, split across 44 inkjets and 16 laser models, and 24 are Epson cartridge models. The other 173, which includes every Brother and Canon machine we list plus 45 HP models and every Epson EcoTank, read and meter cartridges without a gate that can stop the printer. Nearly every cartridge printer has a chip; far fewer use it to lock you out.
Do ink tank printers have cartridge chips?
The ink does not. On a bottle-fed tank machine you pour ink into a reservoir from a plain bottle, and there is no chip on the bottle to authenticate or count down. The 24 tank machines in our catalogue are the one design on this site where the whole question disappears. The machine still meters a waste ink pad internally, which fills up over years of printing, so it is not entirely free of counters.
Keep reading
- Firmware DRM tracker which specific models have an authentication gate, model by model.
- HP cartridge not recognized the step by step fix once you know which job failed.
- Says low but the cartridge is not empty overriding the counter on each brand.
- OEM vs compatible vs remanufactured what the reused chip is worth against what it costs.
- Printer rejects compatible ink after an update what to do when it is the authentication row.
- Is the print head in your cartridge or your printer the other component on the cartridge, and the one that does the locking.
- It will not print black and only a colour is empty the chip counts ink as well as authenticating it, and only one of those stops you here.
- Waste ink pads and maintenance boxes a maintenance box carries a chip too, and the printer reads it the same way.
Sources
- HP, Printer security and secure cartridges, for the statement that Original HP office printer cartridges introduced since 2015 use smart card technology allowing a secure transaction between printer and cartridge, that the chips contain tamper-resistant proprietary HP firmware which helps reduce the risk of malicious code entering the cartridge chip, that the technology is the kind found on chip-based credit and debit cards, and the ISO/IEC 20243 product integrity certification. hp.com
- HP Support, Dynamic Security Enabled Printers, for the statements that dynamic security relies on the printer's ability to communicate with the security chips or electronic circuitry on cartridges, that such printers are intended to work only with cartridges having new or reused HP chips, that reused, remanufactured and refilled cartridges reusing the HP chip are unaffected, and that the authentication process can change over the life of the printer so a non-HP chip may work for a period and then cease to function. hp.com
- HP Support, HP Inkjet Printers, Dynamic Security Feature Affecting Cartridges Using a Non-HP Security Chip, for HP's description of which cartridges are blocked. hp.com
- Epson Official Support, Product Status Messages, for the cannot recognize ink cartridge message, the non-genuine cartridge warning text, and Epson's note that firmware updates may affect the functionality of third-party ink and that non-Epson branded or altered cartridges that functioned before an update may not continue to function. epson.com
- Epson Support, Checking the Ink Cartridge Status, for the note that ink cartridge status may not be displayed when non-Epson cartridges are installed. epson.net
- Canon USA Support, Support Code 1731 Is Displayed, for the procedure of holding the Stop button for at least five seconds to disable the remaining ink level detection function and continue printing. usa.canon.com
- Canon USA Support, disabling the remaining ink detection function, for the same override procedure documented separately. usa.canon.com
- Ars Technica, HP CEO says blocking third-party ink from printers fights viruses, January 2024, for Enrique Lores' claim to CNBC that viruses can be embedded in cartridges and reach the printer and network, and for the security researchers' responses describing the scenario as requiring a nation state tailored attack and as implausible even in a laboratory setting. arstechnica.com
- HP Support, Notice of Proposed Class Action Settlement on Dynamic Security in certain LaserJet printers, for confirmation that the authentication policy extends to laser toner as well as inkjet. hp.com
Last updated . This guide is general information, not a repair warranty. Printer menus and HP's model lists change, so confirm the exact steps for your model on the manufacturer's support site before you make changes.