Xenon headlamp, US/CA
The light switch (10) is connected to BCM. When the switch is in position 2, BCM sends the bus message "Dipped beam button active ON". The dipswitch is integrated in CIM. When it is moved to its rear position (2), CIM sends the bus message "Main beam, stalk active ON".
The bus message "Main beam, stalk active ON" is used by UEC, which lights main beam by supplying B+ voltage from control module pin 35 to pin 10 of the headlamps while the outputs for dipped beam are active. Each headlamp is grounded in the body on pin 1.
When voltage is supplied to headlamp pin 10, the screen in front of the Xenon lamp drops down to produce a main beam image.
The H7 bulb is not lit while the Xenon lamp produces a main beam image.
BCM receives the bus message "Main beam, stalk active" and sends the bus message "Main beam indicator active" to MIU (540). MIU lights the lamp (47g) that indicates that main beam is lit.
While the ignition key is turned to the START position (+50), main beam is off. Main beam lights again once the engine has started or once the ignition key has been turned to the ON position.