Power Distribution Modules

There are three electrical modules, a main power distribution module (PDM) located under the hood on the driver's side above the fender, a chassis module located between the frame rails, and a cab module located to the left of the driver under the switch panel.

The main PDM distributes battery power to the vehicle's control modules and contains the fuses required to protect the power feed circuits to the control modules. See Fig. While the main PDM provides power to the modules, the modules themselves control power flow and circuit protection to the various components of the vehicle electrical systems. Because of this, traditional PDM devices such as relays and circuit breakers are no longer necessary on the main PDM.

Inside the lid of the fuse box there is a sticker that shows the locations of the fuses and describes the circuit(s) that each fuse protects. Fuse configuration will vary depending on the PDM assembly installed. See Fig.. See Table. for descriptions of a typical set of fuses.

Because the electrical system is multiplexed, no relays are needed. The multiplexing module performs the functions normally provided by relays.

Bulkhead Module

Main PDM

Fig. 1, Location of the Main PDM (under driver side hood, above fender)

Battery Power Mega Fuse 1

Battery Power Mega Fuse 2

Engine Harness (green)

Forward Chassis Harness (blue)

Forward Chassis Harness (gray)

Frontwall Harness (black)

Fig. 2, Main PDM (top view)