Diagnosis
The Brother MFC-J4335DW utilizes a chip-based monitoring system to track ink levels. When the "Ink Empty" or "Replace Ink" message persists after a cartridge swap, it indicates a communication failure between the gold-plated contact points on the LC401 ink tank and the internal sensor pins of the printer carriage. This is often caused by a microscopic layer of oxidation, ink residue, or a cartridge that is not seated deep enough into the slot to trigger the physical "detected" switch. Furthermore, the MFC-J4335DW employs a software-level ink counter. If the printer was powered off during the replacement process or if the "Ink Low" warning was ignored for too long, the internal logic may fail to trigger the "Reset" command upon the installation of the new tank. You can confirm this by checking if the error message is "Ink Empty" (indicating a chip read error) versus "Ink Low" (indicating the printer sees the tank but thinks it is nearly empty).
How to Fix It
Follow these precise steps to force the printer to recognize the new INKvestment tanks:
- Power the printer on and wait for the home screen to load. Open the ink cartridge cover.
- Remove all four ink tanks (Black, Cyan, Magenta, Yellow).
- Inspect the gold contact chips on each LC401 tank. Use a lint-free cloth lightly dampened with 90% isopropyl alcohol to wipe the gold contacts. Ensure there are no ink smears or fingerprints on the chips.
- Inspect the printer's internal contact pins inside the carriage. If you see any leaked ink on the pins, gently clean them with a dry cotton swab.
- Reinsert the tanks one by one. Push the tank firmly into the slot until you feel a distinct mechanical "click." If the tank feels "spongy" or doesn't snap in, it will not trigger the sensor.
- Close the ink cover and wait for the printer to perform its initialization sequence. You will hear a loud churning noise for 30-60 seconds as the pump primes the ink lines.
- If the error persists, press the [Home] button, then navigate to [Settings] > [All Settings] > [Ink] > [Ink Volume]. Manually check if any specific color is still showing as empty.
If That Didn't Work
- Perform a "Hard Power Reset." While the printer is on, pull the power cord directly from the back of the machine. Wait exactly 60 seconds. While unplugged, hold the power button for 10 seconds to discharge internal capacitors. Plug the unit back in and restart. This often clears the volatile memory (RAM) and forces a fresh chip read.
- Check for "Non-Genuine" warnings. If you are using third-party compatible tanks, the MFC-J4335DW may reject the chip. When the "Unable to detect ink" message appears, press the [Stop/Exit] button or the [X] button on the touchscreen to bypass the warning and force the printer to attempt printing.
- Execute a Print Head Cleaning. Navigate to [Settings] > [All Settings] > [Ink] > [Cleaning]. Select "All" and run the cycle. Sometimes the printer requires a physical flow of ink through the nozzles to verify that the tank is actually full before it clears the "Empty" status from the display.
- Verify the tank seal. Ensure the orange plastic protective caps were completely removed from the nozzles of the new LC401 tanks. If a piece of the plastic seal is still clinging to the tank, it can prevent the cartridge from seating deep enough to engage the electronic contacts.
Heads Up
- Avoid using "refill kits" that involve syringes on the LC401 tanks; these often damage the chip and will cause permanent "Ink Empty" errors that cannot be reset without replacing the entire tank.
- Always keep the printer plugged into a surge protector. Power spikes can fry the ink-sensing circuitry in the carriage, leading to "Unable to detect ink" errors regardless of the cartridge used.
- If you experience frequent "Ink Empty" errors with genuine Brother ink, check for ink leaks around the carriage area. Excess ink can seep into the contact pins, creating a short circuit that tricks the printer into thinking the tank is missing.