Generator runs but E08 is displayed and output voltage is too high

Safety first: Disconnect all loads and open the main breaker. Turn OFF the generator and disconnect battery negative before accessing internal components.

• Verify with a meter: Use a true RMS multimeter at the output lugs to confirm actual voltage. If the panel reading is wrong but meter is normal, the issue may be with the display, not the AVR.
• Inspect sense wiring: Trace the small gauge wires from the alternator output to the AVR and control module. Repair any damaged or loose connections.
• Check AVR settings: Some DuroMax standby units have an adjustable AVR. Refer to the service manual and adjust the voltage trim pot slightly while monitoring output with a meter. Do not exceed rated voltage.
• Replace AVR if unstable: If voltage fluctuates wildly or remains high despite adjustment, replace the AVR with the correct DuroMax part number.
• Controller fault: If a new AVR does not resolve the issue, the main control module may be misreading voltage and commanding incorrect excitation. This typically requires professional diagnosis and controller replacement.