High Beam Indicator
The blue high beam indicator is a distributed function between the
BCM and the instrument cluster. The BCM reads the high beam bulb voltage, and divides by the system voltage in order to determine a percent value. This value is compared against a calibration in order to determine if the high beams are on. The BCM then transmits the status of the high beams to the instrument cluster via the Class 2 serial data bus. The instrument cluster then commands the high beam indicator accordingly. In the event of a Class 2 data link failure, the high beam indicator will not illuminate unless the indicator was illuminated prior to the Class 2 data link failure.