Charger shows E04 and does not start; sometimes occurs after a lightning storm or power surge.

Safety first: Turn OFF the breaker. Overvoltage conditions can damage equipment and pose shock hazards.

• 1. Verify supply voltage: Have a qualified electrician measure the line-to-line and line-to-ground voltage at the charger input. For most Besenergy Level 2 chargers, this should be around 208–240 VAC. If significantly higher, correct the supply wiring.
• 2. Inspect input wiring: With power OFF and cover removed, check that L1, L2, and ground are correctly landed and firmly tightened. Look for signs of arcing or heat damage at terminals.
• 3. Check surge protection components: Many Besenergy chargers use MOVs or surge modules on the input board. If any are cracked, discolored, or burnt, the input/surge board should be replaced.
• 4. Reset the charger: After correcting any wiring or supply issues, leave the charger powered off for 5–10 minutes to allow internal protection circuits to reset. Then restore power and check if E04 clears.
• 5. Persistent E04: If the supply voltage is normal and wiring is correct but E04 remains, the main control board or input/surge board has likely been damaged by a surge and must be replaced.

When to call a professional: Overvoltage diagnosis and repair should be handled by a licensed electrician or EVSE technician.