NHTSA ID Number: 10183207
Manufacturer Communication Number: 20NA209
TSB/Document Date: 2020-11-30
Summary
This technical bulletin provides repair information to correct a customer concern of Service 4WD Message illuminated on Driver Information Center (DIC), DTCs C118D, C119B and/or C119C set.
Bulletin No.:
Service Bulletin
Date:
20-NA-209
October, 2020
TECHNICAL
Subject:
Service 4WD Message Illuminated on Driver Information Center (DIC), DTCs C118D,
C119B and/or C119C Set
Brand:
Model:
Model Year:
from
to
Silverado 2500HD/
3500HD
2019
2020
Sierra 2500HD/
3500HD
2019
2020
Involved Region or Country
VIN:
from
All
All
to
North America, Israel, Saudi Arabia, Chile
Additional Options (RPOs)
Condition
Some customers may comment on seeing a Service 4WD message illuminated in
the DIC,
Technicians may find DTCs C118D, C119B and/or C119C Set.
Cause
The cause of the condition may be water intrusion and corrosion within the front
differential actuator connector and the electrical harness connector terminals.
Correction
5660054
Scan for DTCs and verify if C118D, C119B, and / or C119C are present. If any of the listed
DTCs are present, inspect the front drive axle actuator electrical connector for signs of
moisture, corrosion at the pins, or damage to the actuator housing.
Note: Examples of damage to the actuator housing and the harness connector seal, are
shown at the start of the Service Procedure below.
Also inspect the electrical wire harness connector for any damage to the internal seal or
signs of moisture and corrosion. If any of the listed conditions such as moisture,
corrosion, or damage are present on either component, replace BOTH the front drive axle
actuator and the electrical wiring harness that connects to the actuator.
Copyright 2020 General Motors
LLC. All Rights Reserved.
Page 2
October, 2020
Bulletin No.: 20-NA-209
Service Procedure
5660055
Electrical Harness Connector Seal Damage
5660056
Front Drive Axle Actuator Housing Damage
Bulletin No.: 20-NA-209
October, 2020
Page 3
5233270
Page 4
October, 2020
Bulletin No.: 20-NA-209
1. Remove the left front tire and wheel assembly, and
the left front wheelhouse liner (3). Refer to Front
Wheelhouse Liner Replacement, in SI.
5334967
2. Remove the underbody skid shield and the front
drive axle actuator (1). Refer to Front Drive Axle
Actuator Replacement, in SI.
5660058
Bulletin No.: 20-NA-209
October, 2020
Page 5
3. Working from the lowest point upward, remove the
front drive axle actuator harness assembly. Note
the harness routing and original location of the
retainers and disconnect the retainer adjacent to
the shock mount last.
5660059
Note: There are seven retainers that secure the
harness to the vehicle.
4. Connect the retainer adjacent to the shock mount
first, then route and install the new front drive axle
actuator harness.
Page 6
October, 2020
Bulletin No.: 20-NA-209
5334967
5. Install the new front drive axle actuator (1) and
reinstall the underbody skid shield. Refer to Front
Drive Axle Actuator Replacement, in SI.
Bulletin No.: 20-NA-209
October, 2020
Page 7
5233270
6. Reinstall the left front wheelhouse liner (3) and the
left front tire and wheel assembly. Refer to Front
Wheelhouse Liner Replacement, in SI.
7. Remove the support and lower the vehicle.
Parts Information
Causal
Part
Description
Part
Number
Qty
X
ACTUATOR ASM-FRT DRV AXLE
84756932
1
X
HARNESS ASM-TRFER CASE SEL SHFT
CONT SW W
84801336
1
Warranty Information
For vehicles repaired under the Powertrain coverage, use the following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH) for coverage information.
Labor Operation
Description
Labor Time
3087168*
Front Drive Axle Actuator and Electrical Harness Replacement
1.3 hr.
*This is a unique Labor Operation for Bulletin use only.
Version
1
Modified
Released October 23, 2020
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
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TSB/Document ID: 20NA209
Replacement Service Bulletin Number:
MFR Communication Date: 2020-10-23
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM
MFR Component System:
MFR Component Subsystem:
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