Charger shows E12; display may indicate "relay check failed" or similar; unit refuses to energize output.

Safety first: Turn OFF power and verify with a tester. Do not attempt to use a charger that fails its self-test.

• 1. Internal inspection (qualified only): With power OFF, open the charger and locate the main relay/contactor. Inspect for signs of overheating, melted plastic, or discoloration.
• 2. Continuity test: Using a multimeter, check continuity across the relay output terminals with the charger powered off. There should be no continuity. If continuity is present, the relay is welded closed and must be replaced.
• 3. Check feedback wiring: Some Besenergy models use a feedback line from the relay output to the main board. Ensure this wire is intact and properly connected.
• 4. Replace relay: If the relay is welded or mechanically stuck, replace it with the exact Besenergy-specified part. Ensure proper torque on all high-current connections.
• 5. Board-level issue: If the relay is mechanically sound and wiring is correct, the relay check circuit on the main control board may be defective and the board should be replaced.

When to call a professional: Relay and high-current work should be done by a qualified technician.