Failure Cause: The control system did not receive data feedback from the spray system, triggering an alarm.
Troubleshooting Steps:

1. Replug and inspect the spray wiring harness connected to the main control unit (MCU). If unresolved, replace the MCU.
2. For "No Communication" or flow meter disconnection:
   • Hover for 30 seconds. If communication is not restored, initiate return-to-home (RTH).
   • If communication recovers within 30 seconds, operations will automatically resume.