E20
Andersen Auxiliary Power Supply Failure

Charger shows E20; app reports 'Internal Power Supply Fault'.

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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

Failed low‑voltage power supply module on main control PCB, Surge or lightning damage, Short circuit on low‑voltage harness to sensors or communication module, Overheating of PSU components

How to Fix / Troubleshooting

Safety first: Internal PSU faults can present a shock or fire risk. Turn off the charger at the consumer unit and do not use it until repaired.

User actions:

  • Isolate power and leave the unit off.
  • Contact Andersen support or a qualified EV technician.

For a technician:

  • With power isolated, open the unit and visually inspect the main control PCB for burnt components, bulging capacitors, or discoloration around the PSU section.
  • Test low‑voltage rails (e.g. 5V, 12V) with the board powered on a test bench if procedures allow.
  • Replace the main control PCB if the PSU section is defective; component‑level repair is generally not recommended without manufacturer guidance.
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Repair Difficulty

Professional Required 5/5

Required Part

Main Control PCB (Auxiliary PSU)
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