20NA218 Service Bulletin/Repair Instructions

Service Bulletin
Bulletin No.:
20-NA-218
Date:
May, 2021
TECHNICAL

Subject:

Brand:
Buick
Cadillac
Possible Crank No Start or Extended Crank with DTC P12A6

Model:
Engine:
from
to
Encore GX
2020
2021
SOP
March

6, 2021
1.2L (LIH)
Regal
2019
2020
—
—
1.5L (LFV)
CT5
2020
2020
—
—
3.0L (LGY)
2021
2021
SOP
November

4, 2020
5.3L (L84),

6.2L (L87)
Camaro
2021
2021
SOP
February

15, 2021
2.0L (LTG)
Corvette
2020
2020
—
—
6.2L (LT2)
2021
SOP
January

14, 2021
1.5L (LYX)
2021
SOP
January

15, 2021
Escalade
Equinox

Malibu
2020

2019

2021
2.0L (LTG)
2019
2019
—
—
LV3, L82,

L84, L87.
Silverado 1500
2020
2021
SOP
February

11, 2021
4.3 (LV3) 5.3

(L82, L84)

6.2 (L87)
Silverado

2500HD/3500HD
2020
2021
SOP
February

11, 2021
6.6 (L8T)
2021
2021
SOP
November

4, 2020
5.3L (L84),

6.2L (L87)
Trailblazer (VIN M)
2020
2021
SOP
March

6, 2021
1.2L (LIH)
Sierra 1500

(New Model)
2019
2019
—
—
LV3, L82,

L84, L87.
Sierra 1500
2020
2021
SOP
February

11, 2021
4.3 (LV3) 5.3

(L82, L84)

6.2 (L87)
Sierra

2500HD/3500HD
2020
2021
SOP
February

11, 2021
6.6 (L8T)
Terrain
2020
2021
SOP
January

14, 2021
1.5L (LYX)
2021
2021
SOP
November

4, 2020
5.3L (L84),

6.2L (L87)
Tahoe
Yukon

Yukon XL
Copyright 2021 General Motors LLC. All Rights Reserved.
Transmission:
1.5L (LFV)
Silverado 1500

(New Model)
Suburban
GMC
Breakpoint Date:
to
Escalade ESV
Chevrolet
Model Year:

from
—
Page 2
May, 2021
Bulletin No.: 20-NA-218
Involved Region or Country
North America, Europe, Uzbekistan, Russia, Middle East, Palestine, Israel, Brazil, Chile,

Paraguay, Colombia, Ecuador, Peru, Uruguay, Argentina, Japan, Thailand, GM Korea

Company, Cadillac Korea (South Korea), Australia/New Zealand, Egypt, other Africa
Condition
Some customers may comment on a possible crank no start or extended crank.

Technicians may find DTC P12A6 set current or in recent history. This could be

accompanied with a crank no start or extended crank issue and additional DTCs P00C6,

P00F4, P0098, P2199 and/or P0096.
Cause
The cause of the condition may be a software anomaly in the Engine Control

Module (ECM).
Correction
Reprogram the ECM.
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 12V 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.

Caution: Be sure the VIN selected in the drop down

menu (1) is the same as the vehicle connected (2)

before beginning programming.
Bulletin No.: 20-NA-218
May, 2021
Page 3
5743643
5644477
Page 4
May, 2021
Bulletin No.: 20-NA-218
5431207
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 Information section of this bulletin.
Important: When programming a module in GM’s new

Vehicle Intelligence Platform, or VIP, the power mode

(ignition) needs to be off or errors may occur. This

involves the 2020 Chevrolet Corvette, Cadillac CT5 and

CT4, as well as the upcoming full-size Chevrolet, GMC,

Cadillac SUVs and Buick Envision. Serial Data

Message Authentication also needs to have the

ignition off.

1. Reprogram the Engine Control Module (ECM).

Refer to K20 Engine Control Module: Programming

and Setup in SI.
Bulletin No.: 20-NA-218
May, 2021
Page 5
5644478
5431209
Page 6
May, 2021
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 SPS Warranty Claim Code (WCC) screen shown

above on the job card. Refer to callout 1 above for the

location of the WCC on the SPS screen.

2. Record the SPS Warranty Claim Code on the job

card for warranty transaction submission.
Warranty Information

Important: Warranty coverage code E2 applies for this

module programming event. ECM reprogramming is

covered for 8 years/80,000 miles (U.S.) or 8 years/

130,000 km (Canada).

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

2887038*
Description
Labor Time
Engine Control Module

Reprogramming for Crank

No Start or Extended Crank

Condition
0.3 hr
Labor

Operation
Bulletin No.: 20-NA-218

Description
Labor Time
*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 SPS Warranty Claim Code was not recorded on

the Job Card, the code can be retrieved in the SPS

system as follows:

1. Open TLC/TIS on the computer used to program

the vehicle.

2. Select and start SPS/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.
Bulletin No.: 20-NA-218
May, 2021
Page 7
Version
10
Modified
Released November 17, 2020

December 18, 2020 – Added 2020 Truck Models and updated programming information

in the Service Procedure.

January 15, 2021 – Added the 2020 Chevrolet Corvette and North America to the

Involved Region or Country section.

February 08, 2021 – Added 2020 Cadillac CT5, 2019 Chevrolet Silverado 1500 and GMC

Sierra 1500 and engine RPOs.

February 23, 2021 – Added the 2021 Model Year to Chevrolet Silverado 1500, 2500HD/

3500HD and GMC Sierra 1500, 2500HD/3500HD with Breakpoint dates, updated the

Condition section with additional DTCs and updated the Involved Region or Country

section.

March 08, 2021 – Added 2021 Buick Encore GX and Chevrolet Trailblazer (VIN M) with

breakpoints.

March 19, 2021 – Added 2020 Buick Encore GX and Chevrolet Trailblazer (VIN M) and

updated the programming template.

April 05, 2021 – Added 2020 and 2021 Chevrolet Equinox and GMC Terrain and added

Brazil to Involved Region or Country section.

April 23, 2021 – Added the Buick Regal and Chevrolet Malibu models, updated the

Involved Region or Country section and updated the programming bullet points under

Service Procedure.

May 07, 2021 – Added the Chevrolet Camaro and the 2021 Malibu with LTG engine.
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.
WE SUPPORT VOLUNTARY

TECHNICIAN

CERTIFICATION

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