Charger shows E04 and does not energize; vehicle may show ‘Line Voltage Error’ or ‘Incorrect Supply’.

Safety first: De‑energize the charger at the breaker. Use a properly rated multimeter and follow local electrical codes. If you are not qualified, contact an electrician.

• Verify supply configuration: Confirm that the Polestar home charger is wired according to its rating (e.g., single‑phase 230 V or three‑phase 400 V). Compare the installation manual to the actual wiring in the input terminal block.
• Measure line voltage: With the cover removed and power restored (electrician only), measure voltage between line(s) and neutral/earth. Ensure it is within the specified range on the charger’s rating label. Persistent undervoltage or overvoltage must be corrected at the supply.
• Check terminal tightness: Turn power off again and tighten all line and neutral terminals in the Polestar charger’s input block to the specified torque. Loose connections can cause voltage drops and E04 errors.
• Controller diagnosis: If supply voltage is correct and stable but E04 remains, the internal voltage sensing circuit on the main control board may be defective. Board replacement is recommended via an authorized service center.