Charger shows E04 and red LED; charging stops or will not start, often after a storm or power fluctuation.

Safety first: Do not attempt to charge if the supply is unstable. Only a qualified electrician should test live voltages.

• Check other loads: Verify whether other appliances in the property are flickering or behaving abnormally. This can indicate a wider supply issue.
• Inspect supply terminations: With power isolated, check that line and neutral conductors are firmly secured in the charger’s terminal block and in the external isolator. Look for signs of overheating or discoloration.
• Measure supply voltage (electrician only): With appropriate test equipment, measure L‑N and L‑E voltages at the charger. Confirm they are within Rolec’s specified range (typically around 230 V ±10% in the UK/EU).
• Check neutral integrity: A loose or broken neutral can cause significant over/undervoltage. Tighten or repair as required at the consumer unit and isolator.
• If supply is stable but E04 remains: The internal voltage sensing circuit on the Rolec control PCB may be defective. Replace the control PCB following Rolec’s service instructions.