Dimmable Backlighting

WARNING: This page is about a different car, the 2009 Ford Pickup, 2009 Ford F550 Super Duty, 2009 Ford F450 Super Duty, and 2009 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

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 MS-CAN to the audio control module (ACM) (except base AM/FM), the rear entertainment module (RETM), the climate control module, and the instrument cluster (IC) to indicate the backlighting intensity level. The trailer brake controller (TBC) receives the message on the HS-CAN from the IC.

If the ACM (except base AM/FM), the RETM, the IC, or the TBC module receives invalid or missing backlighting data from the SJB, the receiving module defaults the backlighting to full intensity.

If the climate control module receives invalid or missing backlighting data for 5 seconds or less from the SJB, the climate control module defaults to the last setting received. If the climate control module receives invalid or missing backlighting data for more than 5 seconds from the SJB, the climate control module defaults the backlighting to full intensity.