It's typical that the SKIM would no longer allow the engine to crank after several attempts of starting the ignition with an invalid key. It's a lock out feature of the module. On the other hand, what's the story about the locking your windows and messing with your gauges while you drive?. This may or may not be relevant but i need some details. I've attached the SKIM functions and operations so that you could relate to how it works. Make sure you check all the fuses under the hood(PDC) and under the dash and replace the ones that are burnt before proceeding. I am also confused that the dealership would rule out the theft system as an issue if the red indicator lamp is staying on in the cluster after a self test. This nagates the troubleshooting procedure. The SKIM module is a module by itself and is NOT a part of the cluster. Was there any DTC's pulled by the technician at the dealership?.
The Sentry Key Immobilizer Module (SKIM) contains a Radio Frequency (RF) transceiver and a central processing unit, which includes the Sentry Key Immobilizer System (SKIS) program logic. The SKIS programming enables the SKIM to program and retain in memory the codes of at least two, but no more than eight electronically coded Sentry Key transponders. The SKIS programming also enables the SKIM to communicate over the Programmable Communications Interface (PCI) data bus network with the Powertrain Control Module (PCM), the Electro-Mechanical Instrument Cluster (EMIC), the Body Control Module (BCM) and/or the DRB scan tool.
The SKIM transmits and receives RF signals through a tuned antenna enclosed within a molded plastic ring formation that is integral to the SKIM housing. When the SKIM is properly installed on the steering column, the antenna ring is oriented around the circumference of the ignition lock cylinder housing.
For added system security, each SKIM is programmed with a unique "Secret Key" code and a security code. The SKIM keeps the "Secret Key" code in memory and sends the code over the PCI data bus to the PCM, which also keeps this code in its memory. The SKIM also sends the "Secret Key" code to each of the programmed Sentry Key transponders. The security code is used by the assembly plant to access the SKIS for initialization, or by the dealer technician to access the system for service. The SKIM also stores in its memory the Vehicle Identification Number (VIN), which it learns through a PCI data bus message from the PCM during initialization.
The SKIM and the PCM both use software that includes a rolling code algorithm strategy, which helps to reduce the possibility of unauthorized SKIS disarming. The rolling code algorithm ensures security by preventing an override of the SKIS through the unauthorized substitution of the SKIM or the PCM. However, the use of this strategy also means that replacement of either the SKIM or the PCM units will require a system initialization procedure to restore system operation.
For diagnosis or initialization of the SKIM and the PCM, a DRB scan tool and the proper Diagnostic Procedures manual are required. The SKIM cannot be repaired and, if faulty or damaged, the unit must be replaced.
OPERATION
When the ignition switch is turned to the On or Start positions, the SKIM transmits an RF signal to excite the Sentry Key transponder. The SKIM then listens for a return RF signal from the transponder of the Sentry Key that is inserted in the ignition lock cylinder. If the SKIM receives an RF signal with valid "Secret Key" and transponder identification codes, the SKIM sends a "valid key" message to the PCM over the PCI data bus. If the SKIM receives an invalid RF signal or no response, it sends "invalid key" messages to the PCM. The PCM will enable or disable engine operation based upon the status of the SKIM messages.
The SKIM also sends messages to the EMIC over the PCI data bus network to control the SKIS indicator lamp. The SKIM sends messages to the EMIC to turn the lamp on for about three seconds when the ignition switch is turned to the On position as a bulb test. After completion of the bulb test, the SKIM sends bus messages to keep the lamp off for a duration of about one second. Then the SKIM sends messages to turn the lamp on or off based upon the results of the SKIS self-tests. If the SKIS indicator lamp comes on and stays on after the bulb test, it indicates that the SKIM has detected a system malfunction and/or that the SKIS has become inoperative.
If the SKIM detects an invalid key when the ignition switch is turned to the On position, it sends messages to the EMIC to flash the SKIS indicator lamp. The SKIM can also send messages to the EMIC to flash the lamp and to the BCM to generate a single audible chime tone. These functions serve as an indication to the customer that the SKIS has been placed in its "Customer Learn" programming mode. See Sentry Key Immobilizer System Transponder Programming in this group for more information on the "Customer Learn" programming mode.
