E9
MUSTART Internal Hardware Fault / Self‑Test Failure

Display shows “E9” and the charger will not start; sometimes appears after the unit has been dropped or physically impacted.

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Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

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Possible Causes

Damaged main control board, failed internal power supply module, corrupted firmware, cracked solder joints from impact or vibration

How to Fix / Troubleshooting

Safety warning: Do not open the charger housing. Internal components store energy even when unplugged.

  • Power reset: Disconnect the charger from the outlet or switch off the breaker for at least 5 minutes, then restore power and check if E9 clears.
  • Check for physical damage: Inspect the MUSTART housing for cracks, dents, or signs it has been dropped. If the enclosure is damaged, do not use the charger.
  • Stable mounting: Ensure the charger is securely mounted or supported to avoid ongoing vibration or movement.
  • Contact support: E9 typically indicates an internal electronics failure. Contact MUSTART or a qualified service provider for board-level repair or replacement.
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Repair Difficulty

Professional Required 5/5

Required Part

Main Control Board or Internal Power Supply Module
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