Charger makes a loud buzzing or humming noise during charging.

Safety first: Disconnect power before tightening screws or touching internal components.

• 1. Identify noise source:
  • Listen carefully to determine if the noise comes from the relay area, power supply, or housing.
• 2. Tighten hardware:
  • With power off, open the housing.
  • Tighten mounting screws for the relay board, transformer, and any brackets.
• 3. Inspect relay:
  • If the relay itself is buzzing loudly, its coil may be failing.
  • Replace the relay board if noise is excessive or accompanied by heating.
• 4. Damping panels:
  • Ensure the housing cover is properly seated and all screws are installed to reduce vibration.

Mild humming can be normal, but sudden or very loud noise should be investigated to prevent failure.