Epson WF-2750 Not Recognizing CIS or Yellow Cartridge Chip? Causes and Quick Fixes

Question:

I watched your video on fixing chip recognition issues for Continuous Ink System (CIS) setups on the Epson WF-2750. I’ve already replaced the chip, but the printer still fails to recognize the yellow cartridge. What else could be causing this issue?

Answer:

Diagnosing the Chip Recognition Problem on the WF-2750

When your Epson WF-2750 displays a “cartridge not recognized” error—even after replacing the chip—it usually points to an issue with either the CSIC board (Cartridge Status Integrated Circuit board), the firmware, or potentially the mainboard if more serious damage has occurred.

Let's walk through how to diagnose and fix the issue properly.

Step-by-Step Troubleshooting

1. Inspect the CSIC Board (Cartridge Interface Board)

Start by removing the cartridge assembly and closely inspecting the CSIC board, especially the section that corresponds to the yellow cartridge pin set.

Look for:

• Missing pins

• Bent pins

• Ink contamination or corrosion

• Any foreign object obstructing contact between the chip and the board

If you notice a bent or depressed pin, try gently straightening it with tweezers. Even a slight misalignment can prevent chip recognition.

2. Test With a Different Cartridge or Chip

Swap in another yellow cartridge or chip if available—even a partially used OEM cartridge will work for testing purposes.

• If the new cartridge is recognized, the problem is with your original chip or how it’s mounted on the cartridge.

• If the issue persists, continue to the next step.

3. Check for “Shifting Recognition” Patterns (Firmware Symptom)

If you’re seeing a rotating issue—where a different color cartridge is “missing” each time you reseat the assembly—it could be a firmware-level miscommunication.

This issue is pervasive in:

• Printers that have undergone CIS or third-party firmware bypass mods

• Epson models that received a firmware update that locked out chip compatibility

• Slightly off-tolerance chip positions that confuse the logic board

This behavior can trick users into thinking the error is related to one cartridge, when in reality, it’s a broader firmware sensitivity or voltage fluctuation problem affecting the entire chip communication circuit.

4. Evaluate for a Burnt or Damaged Mainboard

If none of the cartridges are recognized, and chip errors occur on all four colors, the most likely culprit is a burnt or partially fried mainboard.

This can happen if:

• A wet or damaged chip caused a short circuit

• The CSIC board became overloaded, transferring the fault to the printer’s logic system

• The printer was turned on or reset during a chip swap

Unfortunately, when this happens, there’s no software fix—the board must be repaired or replaced.

Helpful Tip:

If you're working with a CIS system, be sure the ribbon cable from the chips to the printer is not being pulled too tightly or twisted. Stress on the cable can intermittently break contact between the chip and the board, especially during printing.

Printer Repair Services & DIY Support

Printer troubleshooting can get complex quickly, especially when chip communication and hardware interfaces are involved. That’s why we don’t offer remote repair or one-on-one diagnostic support. However, we do provide in-person printer repair evaluations at our facility:
Printer Repair Service
(https://bchtechnologies.com/printer-repair-service)

Please note that we operate on a first-come, first-served basis, and depending on demand, there may be a few weeks' delay before we're able to examine your printer. We offer both whole-printer repair and part-level diagnostics, depending on what the issue calls for. However, our rates may not always be the most cost-effective option, particularly for older consumer-level models.

We highly encourage users to explore self-repair resources, starting with our BCH Technologies YouTube channel (https://youtube.com/@bchtechnologies). Use the search bar beside the “About” section to locate tutorials specific to your model or issue. With hundreds of repair videos created over the past nine years, it's the most efficient way to find targeted solutions. YouTube may also surface helpful suggestions from other creators working with the Epson chip and CIS challenges.

Thanks again for reaching out, and thank you for trusting BCH Technologies as a resource. We hope this guidance helps you get your WF-2750 printing properly again soon.