22-NA-112

Bulletin No.:
Service Bulletin
Date:
22-NA-112
January, 2024
TECHNICAL
Subject:
Brand:
2020 - 2022 Silverado and Sierra Equipped with Diesel Engine Setting DTCs P20BB or
P20C3
Model:
to
2020
2021
2022
2022
Silverado 2500HD/
3500HD
2020
2022
Sierra 1500
2020
2021
2022
2022
2020
2022
Silverado 1500
Silverado 1500 LTD
(RPO J21, 12th VIN
Digit = 4 or less)
Chevrolet
Silverado 1500 New
(RPO J22, 12th VIN
Digit =5 or greater)
Sierra 1500 Limited
(RPO J21, 12th VIN
Digit = 4 or less)
GMC
Model Year:
from
Sierra 1500 New
(RPO J22, 12th VIN
Digit = 5 or greater)
Sierra 2500HD/
3500HD
Involved Region or Country
VIN:
from
Engine:
Transmission:
to
LM2, L5P
LM2, L5P
United States, Canada, Mexico, Australia, New Zealand
Additional Options (RPOs)
Condition
Some customers may comment on Silverado and Sierra Equipped with Diesel Engine
with a MIL illuminated in the DIC as well as a message stating “Speed will be reduced if it
isn’t serviced” illuminated.
Technicians may find DTCs P20BB or P20C3 set current or in history.
Cause
The cause of the condition may be the diagnostics for the DTC P20BB Reductant Heater
1 Control Circuit Low Voltage and DTC P20C3 Reductant Heater 3 Control Circuit Low
Voltage Test Status has been changed to prevent false setting of the DTCs.
Correction
Reprogram the DEF (Diesel Exhaust Fluid) control module with the updated calibration,
refer to the Service Procedure.
• All vehicles require the base software, calibration 87836557.
• Model Years 2020-2022 Heavy Duty Pickup (L5P) require calibration 87836559.
• Model Years 2020-2021 Light Duty Pickup (LM2) require calibration 40009308
• Model Year 2022 Light Duty Pickup (carryover; 12th character of VIN <=4) also require
calibration 40009308
• Model Years 2020-2022 Heavy Duty Cab Chassis (L5P) Regular Cab require
calibration 87836560
• Model Years 2020-2022 Heavy Duty Cab Chassis (L5P) Crew Cab require calibration
87836561
Copyright 2024 General Motors LLC. All Rights Reserved.
Page 2
January, 2024
Service Procedure
Caution: Before downloading the update files, be sure
the computer is connected to the internet through a
network cable (hardwired). DO NOT DOWNLOAD or
install the files wirelessly. If there is an interruption
during programming, programming failure or control
module damage may occur.
• Ensure the programming tool is equipped with the
latest software and is securely connected to the
data link connector. If there is an interruption
during programming, programming failure or
control module damage may occur.
• Stable battery voltage is critical during
programming. Any fluctuation, spiking, over
voltage or loss of voltage will interrupt
programming. Install a GM Authorized
Programming Support Tool to maintain system
voltage. Refer to www.gmdesolutions.com for
further information. If not available, connect a fully
charged 12 V jumper or booster pack
disconnected from the AC voltage supply. DO
NOT connect a battery charger.
• Follow the on-screen prompts regarding ignition
power mode, but ensure that anything that drains
excessive power (exterior lights, HVAC blower
motor, etc) is off
• Please verify that the radio time and date are set
correctly before inserting USB drive into vehicle
for programming, otherwise an error will result..
• Clear DTCs after programming is complete.
Clearing powertrain DTCs will set the Inspection/
Maintenance (I/M) system status indicators to NO.
Bulletin No.: 22-NA-112
Important: The service technician always needs to
verify that the VIN displayed in the TLC left side drop
down menu and the top center window match the VIN
plate of the vehicle to be programmed prior to using
Service Programming System 2 (SPS2) for
programming or reprogramming a module.
• For the TLC application, service technicians need
to always ensure that the power mode (ignition) is
“ON” before reading the VIN from the vehicle’s
VIN master module and that they do not select a
VIN that is already in the TLC application memory
from a previous vehicle.
• If the VIN that shows up in the TLC top center
window after correctly reading the VIN from the
vehicle does not match the VIN plate of the
vehicle, manually type in the VIN characters from
the vehicle VIN plate into the TLC top center
window and use these for programming or
reprogramming the subject module with the
correct vehicle VIN and software and/or
calibrations.
• The Engine Control Module (ECM) is the master
module (for VIP vehicles) that TLC reads to
determine the VIN of the vehicle. If the VIN read
from the vehicle by TLC does not match the VIN
plate of the vehicle, the ECM also needs to be
reprogrammed with the correct VIN, software and
calibrations that match the vehicle’s VIN plate.
• The Body Control Module (BCM) is the master
module (for GEM vehicles) that TLC reads to
determine the VIN of the vehicle. If the VIN read
from the vehicle by TLC does not match the VIN
plate of the vehicle, the BCM also needs to be
reprogrammed with the correct VIN, software and
calibrations that match the vehicle’s VIN plate.
Bulletin No.: 22-NA-112
January, 2024
Page 3
Caution: Be sure the VIN selected in the drop down
menu (1) is the same as the vehicle connected (2)
before beginning programming.
5743643
Important: If the vehicle VIN DOES NOT match, the
message below will be shown
5877000
Page 4
January, 2024
Bulletin No.: 22-NA-112
5644477
Important: Techline Connect and TIS2WEB screens
shown above.
Important: If the same calibration/software warning is
noted on the TLC or SPS Summary screen, select OK
and follow screen instructions. After a successful
programming event, the WCC is located in the Service
Programming System dialogue box of the SPS
Summary screen. No further action is required. Refer to
the Warranty section of the bulletin.
1. Reprogram the DEF through the Reductant Control
Module. Refer to K115 Reductant Control Module:
Programming and Setup in the Service Manual
in SI.
Bulletin No.: 22-NA-112
January, 2024
Page 5
5644478
Note: The screenshots above are an example of
module programming and may not be indicative of the
specific module that is being programmed. Module
selection and VIN information have been blacked out.
Important: To avoid warranty transaction rejections,
you MUST record the warranty claim code provided on
the Warranty Claim Code (WCC) screen shown above
on the job card. Refer to callout 1 above for the location
of the WCC on the screen.
2. Record Warranty Claim Code on job card for
warranty transaction submission.
Page 6
January, 2024
Bulletin No.: 22-NA-112
Warranty Information
Important: LM2 Engine should have 8 year 80,000
mile/130,000 KM emission warranty applied (E2).
Important: L5P Engine should have 5 year 50,000
mile/80,000 KM emission warranty applied (E); this is
the EPA Heavy Duty warranty for vehicles over 8,500
pounds.
For vehicles repaired under the Emission coverage,
use the following labor operation. Reference the
Applicable Warranties section of Investigate Vehicle
History (IVH) for coverage information:
Labor Operation
Description
Labor Time
*2888718
Reductant Control Module Reprogramming with SPS for DEF
with DTCs P20BB or P20C3
0.3 hr
*This is a unique Labor Operation for Bulletin use only.
Important: **To avoid warranty transaction rejections, carefully read and follow the instructions below:
• The Warranty Claim Code must be accurately entered in the “SPS Warranty Claim Code” field of the transaction.
• When more than one Warranty Claim Code is generated for a programming event, it is required to document all Warranty
Claim Codes in the “Correction” field on the job card. Dealers must also enter one of the codes in the “SPS Warranty Claim
Code” field of the transaction, otherwise the transaction will reject. It is best practice to enter the FINAL code provided by
SPS/SPS2.
Warranty Claim Code Information Retrieval
If the Warranty Claim Code was not recorded on the
Job Card, the code can be retrieved in the SPS2
system as follows:
1. Open TLC on the computer used to program the
vehicle.
2. Select and start SPS2.
3. Select Settings.
4. Select the Warranty Claim Code tab.
The VIN, Warranty Claim Code and Date/Time will be
listed on a roster of recent programming events. If the
code is retrievable, dealers should resubmit the
transaction making sure to include the code in the SPS
Warranty Claim Code field.
Version
2
Modified
Released May 24, 2022
Revised January 19, 2024 – Revised the Important Warranty Statements under Warranty
Information.
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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