Controller displays E12 and the generator will not crank; an emergency stop indicator may be lit.

Safety first: Confirm that it is safe to restart the generator and that no maintenance is being performed by others.

• Check emergency stop button: Locate the red E‑stop button on the generator enclosure. If it is pressed in, twist or pull it to release (per label instructions). Verify the E‑stop indicator on the controller turns off.
• Inspect remote stop circuit: If a remote stop/start station is installed, ensure its stop switch is not engaged. Check the wiring from the remote station to the generator for shorts to ground.
• Test E‑stop switch: With power off, disconnect the E‑stop switch leads and test the switch with a multimeter for proper open/closed operation. Replace the emergency stop switch if it remains closed when released.
• Check control wiring: Trace the stop circuit wires in the control panel for pinched insulation or moisture. Repair or replace damaged wiring.
• Clear code and test: After confirming the stop circuit is open (normal), clear E12 and attempt a manual start.