P990 series FAQs and Answers

1. Keyboard Malfunction or Garbled Input

Solution:

• Restart the device to check if functionality resumes.

• If the issue persists (keyboard unresponsive or garbled), replace the keyboard.

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2. Cutter Abnormalities

Possible Causes & Solutions:
If the cutter malfunctions, it may be due to:

1. Faulty Cutter Sensor Board → Return to factory for replacement.

2. Cutter Push Frame Jammed → Manually push the frame. If stuck, apply a small amount of lubricant.

3. Foreign Object in Cutter Gears → Disassemble and clean the gears.

4. Mainboard Issue → Return to factory for inspection/repair.

5. Motor Failure → Replace the motor.

3. Ribbon Depletion or Undetected Consumables

Possible Causes & Solutions:

• Ribbon sensor board failure → Replace the sensor board.

• Ribbon drive roller malfunction → Replace the drive roller.

4. Tube Feeding Issue or Misaligned Cutting (Cutting into Text)

Possible Cause:

• Dirty print roller causing slippage, leading to misalignment or incorrect cutting.

Solution:

1. A. Power off the device.

2. B. Clean the print roller with a cotton swab dipped in alcohol.

3. C. Restart and test printing.

   • If misalignment persists, replace the print roller.

5. Poor Print Quality

Possible Causes & Solutions:

1. A. Dirty Print Head or Roller

   • Clean the print head and print roller with a lint-free cloth and alcohol.

   • If print quality remains poor, proceed to next steps.

2. B. Insufficient Print Head Pressure

   • Disassemble the unit and adjust the pressure spring position on the roller swing arm to increase pressure.

   • (Note: If unsure, return to factory for adjustment.)

3. C. Worn/Damaged Print Head or Roller

   • If the print head is scratched/worn or the roller is worn out, replace the component.

   • (Return to factory for replacement.)

6. No Power (Failure to Boot)

Troubleshooting Steps:

1. A. Check the Power Adapter

   • Use a multimeter to test the adapter’s output voltage.

   • If no voltage is detected → Replace the adapter.

2. B. Inspect Internal Power Connections

   • Open the device and check if the power cable is loose or disconnected.

   • If detached → Reconnect the power cable securely.

   C. Test the Power Button

   • Ensure the button is functioning properly (no physical damage or stuck mechanism).

3. D. Motherboard Failure (Last Resort)

   • If all above steps pass but the device still won’t power on → Return to factory for motherboard inspection/repair.

7. No Text Printed (Blank Output)

Troubleshooting Steps:

1. A. Test the Print Head

   • Replace the print head to check if it’s faulty.

   • If printing resumes → Defective print head (return for replacement).

2. B. Inspect the Motherboard

   • If the print head is functional, check Q3 & Q4 components on the motherboard.

   • If issues are found → Return for motherboard repair.

8. Garbled Text on 4mm² Sleeve (Font Size 5 "W")

Solution:

• Upgrade the firmware and font library to resolve compatibility issues.