Generator controller powers up but shows E0 and will not enter AUTO mode

Safety first: Standby generators can start automatically. Before working on the unit, move the control switch to OFF, open the main AC breaker to the generator, and disconnect the negative battery cable. Only restore power after all covers are reinstalled.

• Check controller mode: Reconnect the battery, turn the controller to OFF, then to AUTO. Some Westinghouse controllers display E0 when no active fault is present but AUTO is not selected.
• Verify configuration: Enter the controller setup menu (refer to your specific Westinghouse standby generator manual). Confirm system voltage, frequency, and exercise timer are set. Save and exit; E0 should clear if it was a configuration placeholder.
• Inspect control wiring harness: With battery disconnected again, remove the controller bezel and gently reseat the multi-pin harness connectors on the back of the controller and at the main control board. Look for bent pins or corrosion.
• Check battery voltage: Measure the 12V battery at rest; it should be around 12.6–12.8 VDC. If below 12.0 V, charge or replace the battery. Low control voltage can cause spurious E0 or prevent AUTO mode.
• Factory reset (if available): Some Westinghouse controllers allow a factory reset from the menu. Perform this only after recording your settings. Reconfigure and test again.

If E0 persists and the unit still will not enter AUTO despite correct configuration and good battery voltage, the controller or main control board may be defective and should be evaluated by a qualified technician.