Theory Of Operation

The Right Steering Wheel Control Switch (Speed Control Switch) includes the Speed Control functions. The Right Steering Wheel Control Switch sends resistor multiplex (MUX) outputs to the Steering Column Module (SCM), indicating specified switch commands. The Right Steering Wheel Control Switch also contains the Local Interface Network (LIN) slave node and communicates the selected states of the Speed Control switch over the LIN Bus circuit to the SCM, which is the LIN master node and a gateway to the Controller Area Network (CAN) Bus network.

U1009-00-LIN BUS 2 FAULT 

This fault is set when the Steering Column Control Module (SCCM) does not receive signals from the Right Steering Wheel Control switch. In this situation, the Right Steering Wheel Control Switch (Speed Control Switch) is either:

• Sending signals over the LIN BUS, but a wiring concern (Short or Open circuit) is preventing the signal from reaching the SCCM.
• Not sending signals over the LIN BUS due to the Right Steering Wheel Control switch not powering up due to power related concerns or a general defect of the switch.
• Sending signals or the LIN BUS with no issues in the switch or the wiring, but the issue lies with the SCCM.

Use the following diagnostics to determine the concern.