Sentry Key Immobilizer System

WARNING: This page is about a different car, the 2016 Dodge Charger and 2015 Dodge Charger. However, it is still accessible from the selected car via links, so may be relevant.

The Sentry Key Immobilizer System (SKIS) 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 FOB with Integrated Key (FOBIK) is used to start the vehicle. The SKIS 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 SKIS uses Low Frequency (LF) Radio Frequency (RF) communication to obtain confirmation that the FOBIK is valid for operating the vehicle.

The microcontroller-based Radio Frequency Hub Module (RFHM) (also known as the RF Hub) contains the SKIS software. The RFHM uses electronic messages over a dedicated Local Interface Network (LIN) data bus to communicate with the ignition switch (also known as the Keyless Ignition Node/KIN) and also uses electronic messages to communicate with other electronic modules in the vehicle over the Controller Area Network (CAN) data bus. Refer to COMMUNICATION, OPERATION .

Pre-programmed Sentry Key FOBIK transponders are provided with the vehicle from the factory. Each RFHM will recognize a maximum of eight Sentry Key FOBIK transponders. If the customer would like additional FOBIK units other than those provided with the vehicle, they may be purchased from any authorized dealer. These additional FOBIK units must be programmed to the RFHM in the vehicle in order for the system to recognize them as valid. This can be done by the dealer using a diagnostic scan tool. All FOBIK units authorized for use in a given vehicle must be present in the vehicle when programming takes place in order to remain valid.

The RFHM performs a self-test of the SKIS each time the status of the ignition transitions out of Off, and will store fault information in the form of a Diagnostic Trouble Code (DTC) if a system malfunction is detected. The RFHM will also send an electronic message to the Instrument Cluster (IC) (also known as the Common Instrument Cluster/CIC) if a fault is detected, and the IC responds by illuminating the security indicator.

The hard wired circuits between components related to the SKIS may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, procedures for proper wire and connector repair, 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 SKIS 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 SKIS or the electronic controls and communication related to SKIS operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.