Charger shows E09 stuck relay or contactor; unit reports energized output when it should be off.

Safety first: A stuck relay can leave the output live unexpectedly. Turn off the breaker and verify with a meter that no voltage is present at the J1772 connector before touching it.

• Confirm output de-energization: With power OFF, disconnect the vehicle and check continuity between line and output terminals of the contactor. If continuity exists with the coil unpowered, the contacts are welded and the main power contactor must be replaced.
• Inspect for wiring bypass: Ensure no wires have been incorrectly landed to bypass the contactor (e.g., line directly to output). Correct any miswiring according to the JuiceBox wiring diagram.
• Visual inspection: Look for melted plastic or discoloration around the contactor. Replace if any damage is visible.
• Board sensing check: If the contactor tests mechanically and electrically sound, but the unit still reports E09, the voltage feedback circuit on the main control board may be defective and require replacement.