Charger displays E14 / ‘Isolation Fault’ and refuses to charge.

Safety first: Do not use the charger until the isolation fault is resolved. Turn OFF the breaker before inspection.

• Inspect for moisture: Check the J1772 connector and cable for signs of water, snow, or condensation. Dry thoroughly with a clean cloth and allow several hours to air dry.
• Check cable integrity: Look for cuts, abrasions, or crushed sections along the cable. If any damage is found, replace the cable/handle assembly.
• Test with another EV: If the error only occurs with one vehicle, the vehicle’s inlet or onboard charger may have an isolation fault—contact the vehicle manufacturer.
• Technician testing: A technician can perform an insulation resistance test (megger) on the charger’s output circuit (with cable disconnected) to confirm insulation health.
• If charger insulation is compromised or isolation circuit is faulty: Replace the J1772 cable and handle assembly and/or the main control board containing the isolation monitor.