03
Thermo King
Warning

Check (Control) Return Air Sensor (Zone)

Failure of the return air sensor, responsible for measuring the cargo temperature.

Possible causes

  • Damaged return air sensor
  • Short or open circuit in sensor wiring
  • Microprocessor input port failure

Recommended actions

  • Compare sensor reading with an external thermometer
  • Verify wiring integrity in the cargo area
  • Replace sensor if resistance is infinite

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