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Security Lamp/Indicator: Description and Operation

The Sentry Key Remote Entry System (SKREES) uses an indicator light to convey information on the status of the system to the customer. This light is shared with the Vehicle Theft Security System (VTSS). The light is located in the instrument panel switch pod, just to the right of the cluster. The indicator light is controlled by the Cab Compartment Node (CCN), via the Controller Area Network (CAN) data bus based upon messages it receives from the Sentry Key Remote Entry Module (SKREEM) on the CAN data bus, and is hard wired to the cluster.

The VTSS/SKREES lamp is controlled according to Sentry Key Remote Entry (SKREEM) messages. Then, the SKREEM sends messages to the Cab Compartment Node (CCN) to operate the light based upon the results of the SKREES self tests. The light may be actuated in two possible ways, flashing or on solid. If the light comes on and stays on solid after a power-up test, this indicates that the SKREEM has detected a system malfunction. If the SKREEM detects an invalid key when the ignition switch is moved to the ON position, it sends a message on the CAN bus to the CCN, to flash the light. The SKREEM can also send a message to flash the light and generate a single audible chime at the same time. These two events occurring simultaneously indicate that the SKREES has been placed into the "Customer Learn" mode. If the light comes on and stays on after the power-up test, diagnosis of the SKREES should be performed using a scan tool and the appropriate diagnostic information. The light is not a serviceable component.