freightliner PX113064S T 2016 Manual Download

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Electric Vehicle Distribution Module (EVDM)

Vehicle power is supplied by the batteries to the
battery cable access (BCA) box. The BCA front wall
pass-through is the primary interface through which
battery power gets transferred from outside the cab
to the inside. It is located on the passenger side of
the front wall. See

Fig. 9.7.

On vehicles equipped with an optional high current
receptacle and/or optional inverter, the BCA has
circuit protection and power cables supplying those
devices. Fuse locations depend on the vehicle and
are outlined on a label on the BCA cover. For an
example see

Fig. 9.8.

The power supplied by the batteries goes to the
electric vehicle distribution module (EVDM) and the
single signal detect and actuation (sSAM) module.

The EVDM is a fuse and relay power distribution
box. It provides power and circuit protection for
powertrain needs, cab functions, and various stand
alone modules. It also supplies power to the
emergency power supply circuits in the event of a
module failure. The EVDM is located in the vehicle
electronics bay, behind the passenger-side dash
panel. See

Fig. 9.7.

Depending on a vehicle’s specifications, the fuses
and relays installed and their locations can vary.
Each EVDM cover is illustrated with an image of the
fuse and relay layout for that vehicle. See

Fig. 9.9

for an example of EVDM cover map of fuses and
relays.

Both the EVDM and the sSAM are grounded at the
cab-side front wall. See

Fig. 9.7.

Cab Electrical and Electronic
Components

Pass-Through Bulkhead Connector

The pass-through bulkhead connector is where the
interior dash harness connects to the exterior chassis
harness. This provides a disconnect point for
harness service, testing, and replacement. It is
located on the driver-side front wall of the vehicle.
See

Fig. 9.7.

Single Signal Detect and Actuation
Module (sSAM)

The single signal detect and actuation module
(sSAM) is the primary module in the electrical
system, combining chassis power distribution, cab
power distribution, and modular switch functions into
a single ECU. The sSAM does

not

contain fuses or

relays.

The sSAM reads input information from sensors,
switches, and databus messages, and drives output
and controller area network (CAN) messages. The
sSAM is located near the center of the cab behind
the lower dash panel. See

Fig. 9.7.

Electronics Bay

The electronics bay contains the electronic control
units that control different vehicle features. It is
located on the passenger-side of the cab behind the
dash panel.

Powernet Management

The powernet management feature protects the
batteries from excessive discharge by disconnecting
certain loads—features that draw power—from the
battery power supply. This allows the batteries to
maintain enough of a charge to restart the vehicle.

Features that draw power are prioritized into different
categories:

House loads: this includes the majority of dash
power outlets.

Basic loads: this includes power for fleet
management systems and third party telematics
as well as critical dash power outlets.

f547630

10/04/2021

Fig. 9.6, Smart Battery Shutoff Switch

Electrical System

9.6