Dimmable Backlighting
When the parking lamps or the headlamps are in the ON position, the SJB monitors the input from the instrument panel dimmer switch. The SJB sends a pulse-width modulated (PWM) voltage to the dimmable components and switches based on input received from the instrument panel dimmer switch. The SJB also sends a message over the controller area network (CAN) to the audio unit, and the instrument cluster (IC) to indicate the backlighting intensity level.
The ACM and IC default to full nighttime brightness if they do not receive the illumination message.