Power Distribution
Warning: Do not attempt to modify, add, splice, or remove electrical wiring on this vehicle. Doing so could damage the electrical system and result in a fire that could cause serious personal injury or property damage.
There are four power distribution modules in the vehicle: the main power distribution module (PDM), the auxiliary PDM, the powertrain PDM, and the powernet distribution box (PNDB).
The main PDM contains the circuit breakers and fuses required to protect the vehicle. It is located in the top of the right-hand dash, and is accessed by removing the four fasteners in the top of the dash panel.
The auxiliary PDM is located on the B-pillar access door, behind the driver's seat. It controls power to the HVAC system, the sleeper, and anti-lock braking.
The powertrain PDM is mounted off the driver's-side frontwall in the engine compartment. It controls power to the engine, aftertreatment system, transmission, and other powertrain-related circuits.
The PNDB is mounted on the cab frontwall near the steering column. It supplies power to the powertrain PDM, the main PDM and other cab functions, including the clock.