Vehicle Power Distribution

4700 dm 09.00.000

There are three standard power distribution modules (PDMs) on vehicles that are compliant with EPA10 and newer regulations: the dash electrical panel, the powertrain PDM, and the powernet distribution box (PNDB). See Fig. for the typical location of the powertrain PDM located in the engine compartment.

Important: The cover on the powertrain PDM unit must be in place to protect against water splash and dust intrusion.

  1. Powertrain PDM

Fig. 1, Powertrain PDM Location

The powertrain PDM houses many of the fuses and relays for the engine, transmission, and aftertreatment system (ATS). There is a label on the cover of the powertrain PDM identifying the fuses and relays.

The PNDB houses up to three MIDI fuses and four ATO fuses. A label on the cover of the PNDB identifies the fuses.

Vehicles may also be equipped with a secondary PNDB. The secondary PNDB sources power to any of the following:

  • fleet management communications

  • trailer end-of-frame connection

  • shore power inverter

  • bodybuilder PDM (housing any fuses and relays necessary for customer-installed truck body equipment)

The main PDMs are located inboard of the passenger-side glove box. Access to the PDMs is achieved by removing the four screws that secure the panel cover. See Fig. and see Fig..

  1. Glove Box

  2. PDM Cover Panel

Fig. 2, Passenger-Side Dash Panels

  1. PDM 1

  2. PDM 2

Fig. 3, Main PDMs

Note:
Parent topic: Electrical System
Document Number: 0000118208
Manual Publication Date: 2024-05-13
Topic Publication Date: 2024-05-16