The disinfection cabinet control board serves as the "brain" of the device, responsible for controlling core functions such as disinfection, heating, drying, and timing. When the control board malfunctions, the entire disinfection cabinet may fail to start, run abnormally, or display error codes, directly affecting the sterilization effect and user experience. This article summarizes the 8 most common faults of disinfection cabinet control boards, along with targeted troubleshooting methods, helping to quickly locate and resolve problems.

1. Control Board Fails to Power On (No Response When the Power Button Is Pressed)

Fault Performance

The indicator light does not turn on, and there is no beep when pressing the power button.

The disinfection cabinet does not perform any function, and the control board has no obvious signs of working.

Possible Causes & Troubleshooting Tips

Power supply circuit abnormality

First, check whether the power cord is plugged in tightly and whether the socket has electricity (test with other electrical appliances). If the socket is faulty, replace the socket or change the power supply position. Check if the power cord is damaged or broken. If the outer skin is cracked or the internal wires are exposed, replace the power cord with the same specification.

Fuse burnout on the control board

Unplug the power supply, open the back cover of the disinfection cabinet, and find the fuse on the control board (usually a small cylindrical component). Use a multimeter to measure the fuse. If the resistance value is infinite, it means the fuse is burned out. Replace it with a fuse of the same rated current (usually 2A–5A for household disinfection cabinets). Note: If the new fuse burns out again immediately, it indicates a short circuit in the control board’s power module (e.g., capacitor breakdown, power chip damage). It is recommended to replace the entire control board at this time.

Power chip damage

If the fuse is intact but there is still no power, check the power chip on the control board for signs of burning (blackening, bulging). If so, contact a professional to replace the power chip or the control board.

2. Key Buttons Are Unresponsive (Buttons Fail to Trigger Functions)

Fault Performance

The indicator light is on, but pressing buttons such as disinfection, drying, and timing has no effect.

Individual buttons are invalid (e.g., the drying button does not work, while other buttons are normal).

Possible Causes & Troubleshooting Tips

Button contact oxidation or damage

For mechanical buttons: Unplug the power supply, remove the control panel, and use alcohol cotton to wipe the metal contacts of the buttons and the circuit board. Oxidation or dust accumulation is the most common cause of button failure. For touch buttons: Check if there is water or oil stains on the touch panel. Wipe the panel clean with a dry cloth. If the touch sensitivity is still poor, the touch chip on the control board may be faulty.

Loose button connection wires

Check whether the connecting wires between the button panel and the control board are loose or fall off. Reinsert the loose plug into the corresponding interface of the control board and fasten it with insulating tape if necessary.

Button circuit damage on the control board

If cleaning and reinserting wires do not solve the problem, use a multimeter to test the button circuit on the control board. If the circuit is open, the control board needs to be replaced.

3. Display Abnormality (Flickering, Garbled Characters, or No Display)

Fault Performance

The display screen flickers continuously, or the numbers/characters are incomplete, garbled.

The indicator light is on, but the display screen is completely black.

Possible Causes & Troubleshooting Tips

Loose display screen connection

Open the control panel, check the connection cable between the display screen and the control board. Reinsert the loose cable to ensure a tight connection.

Display screen backlight failure

If the display has garbled characters but can be faintly seen, it is usually a backlight fault. For LED backlights, check if the LED light strip is damaged; replace the light strip or the entire display module.

Display driver chip damage

If the display is completely black and the connection is normal, the display driver chip on the control board may be faulty. This requires professional testing and replacement of the driver chip or control board.

Moisture intrusion into the control board

Disinfection cabinets often generate water vapor during use. If the control board is not sealed properly, moisture may cause display short circuits. Unplug the power, dry the control board with a hair dryer (low-temperature gear), and then install a waterproof rubber ring on the control panel to prevent recurrence.

4. Disinfection Program Does Not Start (Control Board Sends Commands But the Device Does Not Execute)

Fault Performance

The control board displays the selected program normally, but the disinfection cabinet does not heat up or produce ozone.

The timing function works, but the disinfection function does not activate after the timing ends.

Possible Causes & Troubleshooting Tips

Relay damage on the control board

The control board controls the heating tube, ozone generator, and other components through relays. Use a multimeter to measure the relay’s output voltage. If there is voltage output but the load does not work, the relay is faulty. Replace the relay with the same model (note the coil voltage and contact current of the relay, usually DC12V or DC5V for household models).

Loose connection between the control board and the load

Check the wiring between the control board and the heating tube, ozone generator, and fan. If the wiring is loose, re-fasten the terminal; if the wiring is oxidized, cut off the oxidized part and re-connect.

Faulty load component (not a control board problem)

If the control board has voltage output and the wiring is normal, the fault may lie in the heating tube, ozone generator, or other components. Test the load components separately to rule out non-control board faults.

5. Over-Temperature Protection Triggers Frequently (Device Shuts Down Automatically During Operation)

Fault Performance

The disinfection cabinet stops working suddenly during operation, and the control board displays an over-temperature fault code.

The device can be restarted after cooling down, but the fault recurs quickly.

Possible Causes & Troubleshooting Tips

Temperature sensor signal abnormality

The control board judges the temperature through the NTC temperature sensor. If the sensor is short-circuited or open-circuited, the control board will misjudge the over-temperature. Unplug the power, measure the sensor’s resistance at room temperature (usually 5kΩ–10kΩ). If the resistance is abnormal, replace the temperature sensor.

Faulty over-temperature protection circuit on the control board

If the temperature sensor is normal, the over-temperature protection chip on the control board may be faulty. Contact a professional to replace the protection chip or adjust the protection threshold.

Blocked ventilation duct

Although this is not a control board fault, blocked ventilation can cause excessive temperature and trigger protection. Clean the air inlet and outlet of the disinfection cabinet and avoid stacking tableware too densely.

6. Error Codes Are Displayed (E1–E6 and Other Codes Flash)

Fault Performance

The control board flashes fault codes such as E1, E2, E3, accompanied by an alarm beep.

Different codes correspond to different faults (refer to the product manual for details).

Common Code Interpretation & Troubleshooting Tips

E1 usually indicates a temperature sensor open or short circuit. To troubleshoot, check the temperature sensor and its wiring, and replace the sensor if necessary. E2 is a sign of chamber over-temperature; clean the ventilation duct first, then check the temperature sensor and relay. E3 points to door switch abnormality; confirm the door is closed tightly, and replace the door switch if needed. E4 represents an ozone generator fault; check the ozone generator’s power supply and wiring from the control board. E5 means power voltage abnormality; use a multimeter to test the input voltage, and install a voltage stabilizer if the voltage fluctuates too much. E6 indicates a drying fan fault; check the fan’s drive circuit on the control board, and replace the fan or drive chip accordingly. Note: The definition of fault codes varies by brand. Prioritize referring to the product manual or contacting the brand’s after-sales service.

7. Control Board Is Damaged Due to Moisture (Burnt Smell or Component Bulging)

Fault Performance

There is a burnt smell when the disinfection cabinet is powered on, and the control board has blackened or bulging components (e.g., capacitors).

The device trips the circuit breaker immediately after being powered on.

Possible Causes & Troubleshooting Tips

Moisture intrusion and short circuit

This is a high-risk fault. Unplug the power immediately to avoid electric shock. Do not use the device continuously. Open the back cover and check the control board for water stains, bulging capacitors, or blackened chips. If the damage is minor, dry the control board with a hair dryer and replace the bulging capacitors. If the damage is severe, replace the entire control board.

Preventive measures

After each use, leave the disinfection cabinet door open for 10–20 minutes to dissipate water vapor. Regularly check the waterproof rubber ring of the control panel. Replace the rubber ring if it is aging or cracked.

8. Timing Function Is Abnormal (Inaccurate Timing or Failure to Automatically Shut Down)

Fault Performance

The set timing time is inconsistent with the actual shutdown time (e.g., set for 30 minutes but shuts down in 10 minutes).

The timing function does not work, and the device runs continuously without automatically shutting down.

Possible Causes & Troubleshooting Tips

Clock chip damage on the control board

The timing function relies on the clock chip. If the chip is faulty, the timing will be inaccurate. Use a multimeter to test the chip’s working voltage. If the voltage is abnormal, replace the clock chip.

Programming error of the control board

If the clock chip is normal, the control board’s program may be lost or corrupted. Contact the after-sales service to re-burn the program or replace the control board.

Key Precautions for Troubleshooting

Safety first: All operations must be performed after unplugging the power supply. Do not touch the control board with wet hands to avoid electric shock.

Do not disassemble blindly: If you are not familiar with circuit knowledge, do not randomly solder components on the control board. It is recommended to contact a professional maintenance personnel.

Replace with matching parts: When replacing fuses, relays, or control boards, use parts of the same model and specification to avoid secondary damage.

Conclusion

Most faults of disinfection cabinet control boards are related to power supply, wiring, and component aging. Through step-by-step inspection from the power supply to the control board components, most common problems can be resolved. For severe faults such as chip damage or program loss, replacing the entire control board is the most direct and effective solution. Regular maintenance (cleaning dust, preventing moisture) can significantly extend the service life of the control board.