AIC 521274.09 – LIN Bus 1 Fault. John Deere AIC System Alert.

AIC 521274.09 (AIC )

Code: 521274.09



This error code, AIC 521274.09, indicates a fault within the LIN Bus 1 system, specifically noting an issue with incorrect or absent messages from the LIN Bus Module at Position D or H. The lack of data received from the LIN Bus 1 network suggests a communication breakdown, potentially caused by a fault in the LIN Bus itself or in the transmitting module. This type of error can lead to incomplete or erroneous data being processed by the AIC control software.


To prevent the malfunction from affecting the overall operation of the vehicle’s systems, the control unit has restricted certain functions to maintain system stability and safety.


  • Begin by inspecting the LIN Bus 1 network, particularly focusing on the modules at Positions D and H, for any signs of physical damage or disconnection that might be disrupting communications.
  • Use diagnostic tools to test the integrity and functionality of the LIN Bus 1 network. Look for breaks or degradation in the communication lines that could be hindering data transfer.
  • Examine the settings and configurations of the LIN Bus modules to ensure they are correctly set up for transmitting data. Check for software updates or patches that might resolve known issues with these modules.
  • If a specific module is identified as faulty, consider replacing or repairing it to restore proper communication within the LIN Bus network.
  • After addressing the physical and configurational aspects of the LIN Bus 1, recalibrate the network and perform a thorough system test to ensure that data is being transmitted and received correctly across all connected devices.


Regular monitoring and maintenance of communication networks like the LIN Bus are critical for the reliable operation of interconnected systems within modern machinery. Addressing issues promptly when they arise helps to minimize the impact on the system’s functionality and ensures continued operational efficiency.