Display shows 'STUCK RELAY' or 'RELAY WELD', EVSE refuses to start charging even after power cycle.

Safety first: Turn off the breaker and verify with a meter that no voltage is present before touching internal wiring. A welded relay can leave the output energized even when the EVSE thinks it is off.

• Step 1 – Confirm output is de-energized: With the EVSE commanded OFF and breaker ON, measure voltage at the J1772 output (L1/L2 to ground). If voltage is present when it should be off, the contactor is likely welded and must be replaced immediately.
• Step 2 – Visual inspection: With power OFF, inspect the main contactor/relay for discoloration, melted plastic, or burn marks. Check that the coil wires are intact and firmly connected to the main board.
• Step 3 – Mechanical test: Gently tap the side of the contactor with an insulated tool and listen for free movement when power is applied and removed (you should hear a distinct click). If it does not move or remains engaged, replace the contactor.
• Step 4 – Verify coil voltage: Confirm that the contactor coil rating (e.g., 12 VDC, 24 VDC) matches the OpenEVSE board output. Using the wrong coil voltage can cause overheating and welding.
• Step 5 – Replace components: If the contactor tests good but the board still reports STUCK RELAY, the relay driver or sense circuit on the main board may be faulty. Replace the main control board.
• Step 6 – Post-repair test: After replacing the contactor or board, run the built-in self-test (if available) and verify that the EVSE can switch the output on and off without errors.