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Sentry Key Immobilizer System - Operation






IMMOBILIZER SYSTEM

The Immobilizer System is designed to provide passive protection against unauthorized vehicle use by disabling the engine after about two seconds of running, whenever any method other than a valid Sentry Key is used to start the vehicle. The Immobilizer System is considered a passive protection system because it is always active when the ignition system is energized and does not require any customer intervention. The Immobilizer System uses Radio Frequency (RF) communication to obtain confirmation that the key in the ignition switch is a valid key for operating the vehicle. The Immobilizer System hardware and software also uses electronic messages to communicate with other electronic modules in the vehicle over the Controller Area Network (CAN) data bus. Communication - Operation.

Pre-programmed Sentry Key transponders are provided with the vehicle from the factory. Each Wireless Ignition Node (WIN) will recognize a maximum of eight Sentry Keys. If the customer would like additional keys other than those provided with the vehicle, they may be purchased from any authorized dealer. These additional keys must be programmed to the WIN in the vehicle in order for the system to recognize them as valid keys. This can be done by the dealer using a diagnostic scan tool or, if Customer Learn programming is an available Immobilizer System feature in the market where the vehicle was purchased, the customer can program the additional keys, as long as at least two valid Sentry Keys are already available. Programming and Relearning

The hard wired circuits between components related to the Immobilizer System may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the Immobilizer System or the electronic controls or communication between other modules and devices that provide some features of the Immobilizer System. The most reliable, efficient, and accurate means to diagnose the Immobilizer System or the electronic controls and communication related to Immobilizer System operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.