Display shows E12; charger refuses to start and may indicate a self-test failure.

Safety: The charger has detected that its own safety checks cannot be completed. Do not bypass or ignore this error.

• Power-cycle: Disconnect from mains for 5 minutes and retry. Sometimes transient conditions can cause a self-test to fail.
• Check environment: Ensure the charger is dry and not exposed to condensation or water ingress.
• Inspect cable and housing: Look for obvious damage, cracks, or signs of impact that could have affected internal wiring.
• If E12 recurs: The internal safety circuits on the main control board or associated wiring are compromised. The unit must be serviced or replaced by an authorized technician.