Transponder Key: Description
WARNING: This page is about a different car, the 2004 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
Each ignition key used in the Sentry Key Immobilizer System (SKIS) has an integral transponder chip (Fig 1 ). Ignition keys with this feature can be readily identified by a gray rubber cap molded onto the head of the key, while conventional ignition keys have a black molded rubber cap. The transponder chip is concealed beneath the molded rubber cap, where it is molded into the head of the metal key. Each new Sentry Key has a unique transponder identification code permanently programmed into it by the manufacturer. The Sentry Key transponder if faulty or damaged, must be replaced.