Generator will not start automatically on utility failure; controller logs E10.

Safety first: Turn OFF the generator and open the transfer switch to isolate from utility. Disconnect the battery negative cable before working on control wiring.

• Verify controller mode: Ensure the WEN controller is set to AUTO mode, not OFF or MANUAL. Consult the user interface menu and confirm schedule and auto‑start settings.
• Check control fuses: Locate the low‑voltage control fuses inside the controller compartment. Test each fuse with a meter and replace any blown control fuse with the same rating.
• Inspect start signal wiring: Trace the low‑voltage harness between the WEN generator controller and the automatic transfer switch (ATS). Look for loose terminal screws, broken conductors, or rodent damage. Tighten and repair as needed.
• Test auto start input: With the battery connected and controller powered, simulate a start signal at the controller terminals (per WEN wiring diagram) and see if the unit attempts to crank. If it starts from a local jumper but not from the ATS, the issue is in the ATS or interconnect wiring.
• Check auto start relay: If the controller indicates a start command but the starter circuit does not energize, the internal auto start relay or output transistor may be faulty. Replace the control board if the relay is not serviceable separately.