Module, Shaft Lock: Operation

The electronic steering lock (ESL) is designed to work in conjunction with the radio frequency hub (RFH) to control a locking bolt that engages a machined slot in the steering shaft to prevent shaft rotation whenever the status of the ignition switch (keyless ignition node/kin) is lock. The ESL can only be unlocked when the presence of a valid fob with integrated key (fobik) unit is detected in the front seat area of the vehicle and the status of the ignition switch is run/start.

The electronic circuitry within the ESL contains all of the logic circuits and components to monitor and control the operation of the shaft locking bolt. The module uses a dedicated local interface network (lin) serial data bus for bi-directional communication with the RFH. If the module detects a problem with the positioning or operation of the locking bolt, it sends an error message to the RFH. The RFH then sets and stores a diagnostic trouble code (DTC) and sends an electronic error message over the controller area network (can) data bus to other electronic modules in the vehicle.

The ESL continuously monitors inputs from the RFH and energizes the electric motor to move the locking bolt to the locked or unlocked position based upon that input. If the RFH indicates that the fobik present in the vehicle is invalid, the locking bolt remains in the locked position. When the RFH indicates that a valid fobik is present in the vehicle and the status of the ignition switch (kin) is run or start, the ESL operates a motor to move the locking bolt to the unlocked position. However, to prevent inadvertent column locking due to a failure while the vehicle is being operated, the module cannot move the locking bolt from the unlocked position to the locked position as long as the status of the ignition switch remains run or start.

The ESL receives a path to ground at all times through a hard wired remote ground point. The module receives battery voltage to operate and to move the locking bolt in the unlocked direction on a b(+) circuit, and receives battery voltage to operate the locking bolt in the locked direction only when the status of the ignition switch is off and other data from the RFH allows it.

For added system security, the ESL learns a unique secret key code from the RFH over the lin data bus upon initialization. This code is stored in the memory of the module and cannot be changed. Therefore, if the RFH requires service replacement, a new ESL will also be required. Another security code, called a pin, is used to gain access to the RFH secured access mode. The secured access mode is required during service to initialize a new ESL. Before replacing the shaft lock module or the RFH see the RFH REPLACEMENT AND PROGRAMMING ORDER GUIDE  for the proper sequence. Refer to STANDARD PROCEDURE .

The hardwired circuits of the shaft lock module may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the shaft lock module or the electronic controls and communication between other modules and devices that provide some features of the skis. The most reliable, efficient and accurate means to diagnose the shaft lock module or the electronic controls and communication related to skis operation requires the use of a diagnostic scan tool.