Sentry Key Immobilizer

The Sentry Key Immobilizer System (SKIS) authenticates an electronically coded Transponder Key placed into the ignition and sends a valid/invalid key message to the Powertrain Control Module (PCM) based upon the results. The "VALID/INVALID KEY" message communication is performed using a rolling code algorithm via the Programmable Communication Interface (PCI) data bus. A "VALID KEY" message must be sent to the Powertrain Control Module (PCM) within two seconds of ignition ON to free the engine from immobilization.