Failure Cause:
Potential short circuit of the flow meter port caused by burnt spray nozzle actuators. This occurs because the main control unit (MCU) internally integrates the spray module control board with the actuator port signal wiring harness.

Troubleshooting Steps:

1. ​Spray Nozzle Actuator Inspection:

   • Short circuits in left-side actuators (tail section) may affect the flow meter.
   • Remove the spray nozzle actuators from the left side of the tail section to inspect for damage.

2. ​Electrical Testing:

   • After removing damaged actuators, power on the aircraft to test.
   • Verify whether the flow meter short circuit was caused by the faulty actuator.