AIC 521275.09 – LIN Bus 2 Fault. John Deere AIC System Alert.

AIC 521275.09 (AIC )

Code: 521275.09



This error code, AIC 521275.09, is issued when there is a disruption in the LIN Bus 2 system, highlighting issues with incorrect messages or a lack of data transmission from the LIN Bus Module at Positions E or M. The absence of data signals a significant communication breakdown, potentially due to faults within the LIN Bus itself or the modules responsible for data transmission.


In response to this communication failure, the control unit has restricted certain functionalities that rely on LIN Bus 2 to prevent further operational issues and maintain system integrity.


  • Inspect the LIN Bus 2 network, particularly at Positions E and M, for any signs of damage, wear, or disconnections that could be affecting communication.
  • Use specialized diagnostic tools to evaluate the transmission and reception capabilities of the LIN Bus 2. Check for any signal interruptions or anomalies that could indicate a fault in the network.
  • Review the configuration and settings of the LIN Bus modules involved to ensure they are properly set up and aligned with system requirements. Apply any necessary updates or adjustments to optimize performance.
  • If a specific module is identified as defective or malfunctioning, replace or repair it to restore full communication capabilities across the network.
  • After making any necessary repairs or adjustments, recalibrate the network and perform comprehensive testing to ensure that communication is fully restored and that all system functionalities dependent on LIN Bus 2 are operating correctly.


Maintaining the efficiency and reliability of LIN Bus networks is crucial for the seamless operation of advanced vehicle systems. Regular checks and prompt resolution of communication issues are essential to prevent disruptions and ensure that all networked components function as intended.