Multiplexed Electrical System Service Manual 4 lifter/pusher axle switches. The eight general switches are inputs into the CECU while the four hardwired switches are wired directly to the air solenoids with no software interlocks or CECU control. For detailed information on the EOA interlocks refer to Electric Over Air Switch Interlocks on page 8-11 in the "How It Works" section of this manual. Exterior Lighting Self Test The Exterior Lighting Self Test (ELST) is intended to be operator activated and used to enhance the vehicle pre-drive inspection. When initiated, the ELST toggles between two exterior lighting sequences. The ELST tests the functionality of certain exterior lights.
The ELST can be activated from a dash switch that is accessible from outside the cab or by the optional remote keyless key fob transmitter. Cab Dimmer The cab dimmer switch is a momentary up/down dash switch that allows the user to raise or lower the dash backlighting illumination levels. The vehicle has a day time brightness setting that is independent of the night time brightness setting. Door Controls The Door Control System (DCS) operates with CECU electrical architecture to enable the user to raise/lower the door windows, lock/unlock door locks, adjust mirror position, and activate mirror heat.
Body CAN There is a dedicated communication line (B-CAN) for customer installed control units. This dataline may be used by body builders to add like protocol control units. For more information regarding the B-CAN, refer to the appropriate Body Builder Manual. PM819023/KM815057 (08/14/2012) 4 - 3