John Deere 516446.09 – AIC (Armrest Interface Control Unit): Armrest Multi-Function Lever Module Message Missing

The Armrest Interface Control Unit (AIC) is failing to receive a LIN (Local Interconnect Network) message from the armrest multi-function lever module (hydraulic joystick), indicating a failure in the LIN Bus communication line or a failure of the transmitting module itself.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 9470RT
• 9520RT
• 9570RT

1. 1

   Confirm that fault code AIC 516446.09 is currently active

2. 2

   Check the wiring harness connecting the Armrest Interface Control Unit to the Multi-Function Lever Module on the LIN Bus 4 network

3. 3

   Inspect the electrical connectors at both the AIC and the joystick/lever module for pushed-back pins, corrosion, or moisture intrusion

4. 4

   Ensure the Multi-Function Lever Module is receiving proper operating voltage and has a solid ground connection

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical shorts during testing.

2. 2

   Access the Armrest

   Carefully disassemble the right-hand armrest console (CommandARM or standard console) to access the internal wiring for the Multi-Function Lever and the AIC module.

3. 3

   Perform Continuity Testing

   Using a multimeter and the machine's specific electrical wiring diagram, test the continuity of the LIN Bus communication wires between the AIC and the Multi-Function Lever.

4. 4

   Repair Wiring (If Applicable)

   If you find an open circuit, short to ground, or high resistance in the wiring harness, repair or replace the damaged section of the harness.

5. 5

   Replace the Module (If Wiring is Good)

   If the wiring harness tests perfectly and the module has verified power and ground, the transmitting LIN Bus module inside the joystick has failed internally. Disconnect and remove the faulty Multi-Function Lever Module.

6. 6

   Install and Reassemble

   Install the new Multi-Function Lever Module, reconnect all electrical plugs, and reassemble the armrest console.

7. 7

   Clear Codes and Test

   Reconnect the battery, turn the key on, clear the stored fault codes, and test the joystick functions (e.g., SCV controls, front loader operation) to ensure communication is restored and the code does not return.