NHTSA ID Number: 10176631
Manufacturer Communication Number: 20NA096
TSB/Document Date: 2020-06-22
Summary
This informational bulletin provides information for dealers/technicians on Glow Plug Control Module Update.
Service Bulletin
Bulletin No.:
20-NA-096
Date:
May, 2020
INFORMATION
Subject:
Brand:
Glow Plug Control Module Update
Model:
Model Year:
VIN:
to
Silverado
2500HD/
3500HD
2020
2020
L5P
Silverado
4500HD/
5500HD/
6500HD
2020
2020
L5D
Sierra
2500HD/
3500HD
2020
2020
L5P
Involved Region or Country
from
Engine:
from
to
All
United States, Canada, Middle East, and Israel
Additional Options (RPOs)
Condition
Copyright 2020 General Motors
LLC. All Rights Reserved.
Some customers may comment that the MIL is illuminated.
Some technicians may find one or more of the following DTCs set in the Engine Control
Module (ECM):
• DTC P066A: Cylinder 1 Glow Plug Control Circuit Low Voltage
• DTC P066B: Cylinder 1 Glow Plug Control Circuit High Voltage
• DTC P066C: Cylinder 2 Glow Plug Control Circuit Low Voltage
• DTC P066D: Cylinder 2 Glow Plug Control Circuit High Voltage
• DTC P066E: Cylinder 3 Glow Plug Control Circuit Low Voltage
• DTC P066F: Cylinder 3 Glow Plug Control Circuit High Voltage
• DTC P0671: Cylinder 1 Glow Plug Control Circuit
• DTC P0672: Cylinder 2 Glow Plug Control Circuit
• DTC P0673: Cylinder 3 Glow Plug Control Circuit
• DTC P0674: Cylinder 4 Glow Plug Control Circuit
• DTC P0675: Cylinder 5 Glow Plug Control Circuit
• DTC P0676: Cylinder 6 Glow Plug Control Circuit
• DTC P0677: Cylinder 7 Glow Plug Control Circuit
• DTC P0678: Cylinder 8 Glow Plug Control Circuit
• DTC P067A: Cylinder 4 Glow Plug Control Circuit Low Voltage
• DTC P067B: Cylinder 4 Glow Plug Control Circuit High Voltage
• DTC P067C: Cylinder 5 Glow Plug Control Circuit Low Voltage
• DTC P067D: Cylinder 5 Glow Plug Control Circuit High Voltage
• DTC P067E: Cylinder 6 Glow Plug Control Circuit Low Voltage
• DTC P067F: Cylinder 6 Glow Plug Control Circuit High Voltage
• DTC P068C: Cylinder 7 Glow Plug Control Circuit Low Voltage
• DTC P068D: Cylinder 7 Glow Plug Control Circuit High Voltage
• DTC P068E: Cylinder 8 Glow Plug Control Circuit Low Voltage
• DTC P068F: Cylinder 8 Glow Plug Control Circuit High Voltage
• DTC P06C5: Cylinder 1 Glow Plug Incorrect
• DTC P06C6: Cylinder 2 Glow Plug Incorrect
• DTC P06C7: Cylinder 3 Glow Plug Incorrect
Page 2
May, 2020
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Bulletin No.: 20-NA-096
DTC P06C8: Cylinder 4 Glow Plug Incorrect
DTC P06C9: Cylinder 5 Glow Plug Incorrect
DTC P06CA: Cylinder 6 Glow Plug Incorrect
DTC P06CB: Cylinder 7 Glow Plug Incorrect
DTC P06CC: Cylinder 8 Glow Plug Incorrect
DTC P1338: Cylinder 1 Glow Plug Offset Exceeded Learning Limit
DTC P1339: Cylinder 2 Glow Plug Offset Exceeded Learning Limit
DTC P133A: Cylinder 3 Glow Plug Offset Exceeded Learning Limit
DTC P133B: Cylinder 4 Glow Plug Offset Exceeded Learning Limit
DTC P133C: Cylinder 5 Glow Plug Offset Exceeded Learning Limit
DTC P133D: Cylinder 6 Glow Plug Offset Exceeded Learning Limit
DTC P133E: Cylinder 7 Glow Plug Offset Exceeded Learning Limit
DTC P133F: Cylinder 8 Glow Plug Offset Exceeded Learning Limit
Cause
The cause of the condition may be a software anomaly.
Correction
Reprogram the Glow Plug Control Module (GPCM) with the latest available software.
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.
Note: Carefully read and follow the instructions below.
•
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.
Turn OFF or disable systems that may put a load
on the vehicles battery such as; interior lights,
exterior lights (including daytime running lights),
HVAC, radio, etc.
Clear DTCs after programming is complete.
Clearing powertrain DTCs will set the Inspection/
Maintenance (I/M) system status indicators to NO.
Bulletin No.: 20-NA-096
May, 2020
Page 3
5431207
Important: TIS2WEB screen shown. Techline Connect
screen is simlar and will be included soon.
Important: If the Same Calibration/Software Warning
is noted on the SPS 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 Glow Plug Control Module. Refer to
K34 Glow Plug Control Module: Programming and
Setup in SI.
Page 4
May, 2020
Bulletin No.: 20-NA-096
5431209
Important: TIS2WEB screen shown. Techline Connect
screen is simlar and will be included soon.
Important: To avoid warranty transaction rejections,
you MUST record the warranty claim code provided on
the SPS Warranty Claim Code (WCC) screen on the
job card. Refer to callout 1 above for the location of the
WCC on the SPS screen
2. Record SPS Warranty Claim Code on job card for
warranty transaction submission.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
*2810055
Glow Plug Control Module Reprogramming with SPS
Use Published Labor
Operation Time
Important: *To avoid warranty transaction rejections, carefully read and follow the instructions below:
• The SPS 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.
Bulletin No.: 20-NA-096
May, 2020
Page 5
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 TIS on the computer used to program the
vehicle.
2. Select and start SPS.
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
1
Modified
Released May 04, 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: 20NA096
Replacement Service Bulletin Number:
MFR Communication Date: 2020-05-05
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ENGINE
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