Operation

OPERATION

The service column lock indicator gives an indication to the vehicle operator when the Wireless Ignition Node (WIN) (also known as the Sentry Key Immobilizer Module/SKIM, the Sentry Key REmote Entry Module/SKREEM or the Wireless Control Module/WCM) has recorded a Diagnostic Trouble Code (DTC) for a steering column shaft lock module circuit or component malfunction. This indicator is controlled by the instrument cluster logic circuit based upon cluster programming and electronic messages received by the cluster from the WIN over the Controller Area Network (CAN) data bus.

The service column lock indicator function of the reconfigurable dot matrix Organic Light Emitting Diode (OLED) display unit is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the OLED service column lock indication will always be OFF when the ignition switch is in any position except ON or START. The instrument cluster will turn ON the service column lock indicator for the following reasons:

- Service Column Lock Indicator Lamp-On Message - Each time the cluster receives an electronic service column lock indicator lamp-ON message from the WIN, the service column lock indicator will be illuminated. The indicator remains illuminated for about five seconds, until the cluster receives a lamp-OFF message from the WIN, until the cluster arbitrator logic determines that another display request has priority, or until the ignition switch is turned to the OFF position, whichever occurs first.

The WIN continually monitors the steering column shaft lock module circuits and components to determine the condition of the system. The WIN then sends the proper lamp-ON or lamp-OFF message to the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN).

For proper diagnosis of the shaft lock module, the WIN, the EMIC, the CAN data bus or the electronic communication related to service column lock indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.