54-354

CPC5 Internal Fuses
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional

Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado

Business Class M2
Cascadia
108SD/114SD
> New Cascadia

Freightliner
Service Bulletin

Description of Revisions: This bulletin replaces the version dated
05/09/2022. The part number for the CPC5 module has been
updated.

General Information
This service bulletin applies to New Cascadia vehicles manufactured after February 21, 2022. Due to a global
supply shortage of circuit protection microchips, the CPC5 module was redesigned to eliminate the circuit
protection microchip. New CPC5 modules uses non-resettable, non-replaceable fuses to protect four sensor
common pins located on the CPC5 module. This change began with CPC5 part number A 055 446 40 02. The
latest CPC5 part number as of this writing is A 055 446 48 02, which replaces all earlier versions. Table 1
provides a description of the impacted CPC5 module circuits and pins.
Impacted CPC5 Circuit and Pins
CPC5
CPC5 Circuit Description
Connector/Pin
VSS Sensor Common
X3/22
Ambient Air Temperature Sensor
X3/35
Common
Accelerator Pedal Position #1 Sensor
X3/29
Common
Accelerator Pedal Position #2 Sensor
X3/43
Common
Table 1, Impacted CPC5 Circuit and Pins

A short-circuit to battery voltage condition in wiring in any of the circuits listed in Table 1 may result in one of
these internal fuses opening. If wiring issues are not isolated and corrected prior to CPC5 replacement,
repeated CPC5 failure may result before the vehicle is ultimately fixed. This must be avoided by proactively
checking the circuits in question prior to replacing the CPC5 module.

CPC5 Module Harness Voltage Check
A vehicle with a suspected faulty CPC5 module (A 055 446 40 02 or A 055 446 48 02) should be checked to
make sure that there are no short to power conditions on any of the four sensor common pins described in
Table 1. A voltage check using a digital multimeter (DMM) should be performed on each pin noted in Table 1
before replacing the CPC5 module. To do this, perform the following steps:
1. Unplug the X3 connector from the CPC5 module.
2. Connect the negative lead of a DMM to a known good ground.
3. Carefully probe pins 22, 29, 35, and 43 in the harness at the X3 connector.
3.1

A voltage reading on any of the pins indicates a short to power. Locate the source of the voltage and
correct the problem.

3.2

If voltage is not present on any of the pins, it is safe to replace the CPC5 module.

Warranty
This is an informational bulletin only. Warranty does not apply.

Freightliner Service Bulletin, 07/29/2022

Page 1