2025 GMC Terrain Elevation
Levels of
Success
The Next Generation 2025 GMC Terrain
New
Territory
Opening the
Tool Box
A Clearer
Vision
Service Repair News
From Your Parts Supplier
IN
SIGHTS
SERVICE
S P R I N G 2 0 2 5
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“
ACDelco Training
is committed
to providing
aftermarket repair
facilities with
relevant and up-to-
date training.”
— John Latner
Manager, ACDelco
Technical Training
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1
CONTENTS
S P R I N G 2 0 2 5
2
PROGRAMS
my GM Partner Perks
has the tools at hand
4
GM GENUINE PARTS/
ACDELCO
Brand tiers diversify
parts lineup
6
ACDELCO
Where the rubber
meets the windshield
8
PRODUCT SPOTLIGHT
The GMC Terrain
takes a solid stance
12
ACDELCO
Go by the book
with course catalog
14
TIPS
Non-GM calibrations
can shake things up
16
TIPS
Address DIC messages
by checking trailer plug
Service Insights magazine is published
quarterly by General Motors. Address all
correspondence to Insights Magazine
Editorial Offices, 3001 West Big Beaver
Rd., Suite 608, Troy, MI 48084.
© 2025 General Motors. All rights
reserved. GM, the GM logo, GM Genuine
Parts, ACDelco, Chevrolet, GMC, Buick,
Cadillac and the slogans, emblems,
vehicle model names, vehicle body
designs and other marks appearing in
this publication are the trademarks and/
or service marks of General Motors, its
subsidiaries, affiliates or licensors. All
information in the publication is based
on the latest information at the time
of publication approval. The right is
reserved to make changes at any time in
prices, rebates or offers. Service Insights
magazine, General Motors, participating
dealers and the publisher of this
magazine are not responsible for prices
or information printed in error.
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GM ADVISOR
John Juarez
GM ADVISORY BOARD
Kent Burnett, Chris Crosby
Stephanie Desrosier, Kelli Doherty
Kyle Edwards, Matthew Ericksen
Jessica Field, Lea George
Matt Gibbard, Bob Gollehur
Marc Hammond, Logan Hill
Zachary Hirsch, Kim LaClear
John Latner, Jacob Lepore
Mike Stachelski, Bob Stewart
EDITOR
Bill Davis
WRITERS
Amy Lenard, Jim Pesta
Mark Spencer
ART DIRECTOR
Mindi Schappach
MAGAZINE DESIGNER
Joe Senneker
GRAPHIC DESIGNER
Gerald Stein
OPERATIONS
Rebecka Bale
CONTACT US AT
editor@ccainsights.com
2025 GMC Terrain Elevation
(shown with available features)
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Right
Tools
The
Key resources
help
the my GM Partner Perks
program
work for you
Program
Management
Tools
The My Toolbox section
located in the
top navigation of the my GM Partner Perks
portal has important tools for program
members, including:
m
y GM Partner Perks is a parts
loyalty program in which,
whether as an independent service
center or body shop, participants enjoy
many benefits, such as rewards* on all
their GM parts purchases, including GM
Genuine Parts and ACDelco, Chevrolet
Performance, and GM Accessories. To
ensure one is getting the most out of
their my GM Partner Perks account, the
My Toolbox section of the program portal
(
myGMPartnerPerks.com
) has several
resources that provide clear information
and direction. Let’s take a look at what
program members can make use of.
PROGRAMS
Business
Click here to review enrollment
details, view your program
agreement, or make updates
to your services and products
stocked.
Employees
This tool allows program
members to manage employee
participation in the program in
a business support, employee,
or co-owner role; business
owners are encouraged to add
an employee in the business
support role.
Sellers
Use this tool to list all ACDelco
Distributors and GM Dealers,
including account numbers,
from whom you buy parts to
ensure you receive credit for all
purchases.
Allocations
Here, participants manage how
rewards get distributed among
their employees.
Forms and Guides
These how-to job aids are
designed to help you get
the most out of the program
independently. They include
tools for updating important
shop information, reading
crucial reports and
redeeming points.
The my GM Partner
Perks Handbook
The my GM Partner Perks Handbook
is a
comprehensive guide that corresponds to
these four pillars of the program:
Rewards & Incentives
—
The
handbook details the wide range of award
redemption options available to my GM
Partner Perks members.
Marketing Support
—
Gain access to
point-of-sale materials, merchandise and
digital support, including website, search
and social media. In addition, enrollees will
have access to the national site-locator
listing on
gmparts.com
designed to help
get their shop in front of more customers.
Repair Resources
—
Members have
access to diagnostic support and Service
Information (Si) to keep their shops and
employees up to date and potentially
save time on repairs.
Profitability & Productivity
—
The handbook reminds participants
that they can provide customers with
peace of mind with programs such as
Consumer Assurance and Roadside
Assistance. Participants also receive
discounts on items such as computer
products, business forms and
credit-card processing that can
help lower operating costs.
Opportunity Report
The my GM Partner Perks Opportunity
Report
allows members to track their
activity in the program and includes a
detailed video that walks members through
how to use the report. Report
information includes:
Detailed
purchase data, including by
product category and product line, and
invoice-level detail.
Program
date and what program level
your shop is enrolled in.
Contact
information for regional
my GM Partner Perks personnel.
n
*Rewards not available for Fleets.
How to Redeem my GM
Partner Perks Points
Members can find the current
balance
of my GM Partner Perks points
in their digital wallet. Members can also
access the rewards catalog by clicking
on the shopping cart from their wallet
on
mygmpartnerperks.com
. Points can
be used several ways:
Rewards Catalog:
Shop from
among the 5,000-plus unique items
in the online Rewards collection, with
new items added every week.
Gift Cards:
Treat team members
or family to more than 130 unique
gift-card brands, including from
major home-improvement outlets,
outdoor stores and nationally known
coffeehouses.
Travel:
Find more than 400,000
hotel properties in 200-plus
countries, 150 major airlines, rental
cars, and approximately 120,000
excursions in 1,300 destinations
globally.
Transfer Points:
– The my GM Partner Perks
exclusively yours (EY) Prepaid
Mastercard* allows members
to shop in-store or online at
approximately 150 popular retailers
and restaurants.
– Choose to cover an eligible
business expense.
– Use rewards points toward the
purchase of a new Chevrolet, Buick,
GMC or Cadillac vehicle.
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Scan the QR code
to enroll or
learn about the program.
*Card is issued by Pathward
®
, N.A., Member
FDIC, pursuant to license by Mastercard
International Incorporated. Mastercard and
the circles design are registered trademarks
of Mastercard International Incorporated.
No cash access or recurring payments. Can
be used at select merchants where Debit
Mastercard is accepted; see eycardonline.
com. Card valid for up to 24 months, funds
do not expire and may be available after card
expiration date, and fees may apply. Terms
and conditions apply.
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T
he battle to help customers keep
repair costs down is a real one.
Looking at what aftermarket
competitors offer may be tempting to
those looking at the bottom line, but do
those customers really save in the long run
when you consider that those parts don’t
go through the same rigorous testing that
GM Genuine Parts and ACDelco do?
GM Genuine Parts and ACDelco are not
just any parts. “GM Genuine Parts and
ACDelco are the same quality products
you’ve come to know and trust because
General Motors backs each part we offer,”
says Jacob Lepore, Global Parts Marketing
Brand Lead. “We do that through intensive
validation of the product and a strong GM-
backed limited warranty.”
*
GM Genuine Parts and ACDelco
meticulously categorize their premium
portfolio of Original Equipment and
aftermarket parts into three tiers: GM
Genuine Parts or ACDelco Original
Equipment, ACDelco Gold, and ACDelco
Silver. This provides you with a
comprehensive understanding of your
options and empowers you to make the
best choice for your customer’s vehicle.
Let’s take a look at what each tier offers.
Original
Equipment
GM Genuine Parts
and
ACDelco Original
Equipment
are the true OE parts
installed during production or validated
by General Motors for GM vehicles.
These maintenance, repair, powertrain
and collision components are designed,
engineered and tested to rigorous
standards for specific vehicles and are
backed by General Motors.
Popular GM Genuine Parts and ACDelco
Original Equipment parts offer a full line of
replacement parts, including spark plugs,
oil filters, brake pads, mirrors, tailgates,
steering wheels, center consoles, tow
hooks, engine cylinder head bolts, trailer
hitches, windows, window switches and
regulators, to name a few.
Designed.
Tested.
Backed
by
General Motors.
GM Genuine Parts
and
ACDelco
offer choices
for customers with a
three-tiered approach
ACDelco
Gold
ACDelco Gold parts
are a high-quality
alternative to OE parts. They are
manufactured to meet fit, form and
function expectations, making them a
smart choice for General Motors vehicles
and most makes and models, including
special applications. These high-quality
parts are backed by General Motors.
ACDelco
Silver
ACDelco Silver parts
are a high-value
option for General Motors vehicles and
most makes and models, all at an attractive
price point, and they are backed by
General Motors.
ACDelco Gold and Silver premium lines
are the only aftermarket parts backed by
General Motors for GM vehicles and most
other makes and models. Gold and Silver
parts include batteries, brake system parts,
filters and suspension parts.
Keep in Mind:
Products may be in
older packaging as inventory continues to
transition to the updated box design. See
the image below to see what the current
packaging looks like. Also, if you suspect
that you have purchased a counterfeit part
or have information regarding counterfeit
activities, please contact the
GM Global Brand Protection Team at
gm_global_brand_protection@gm.com
or
go to
gmparts.com/counterfeit-parts
.
n
*Effective on parts purchased April 1, 2018, and later to the original retail purchaser. Contact seller for limited warranty part details,
qualifications, and possible labor coverage.
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ACDELCO
ACDelco windshield wipers help
owners keep a clean perspective
W
indshield wipers are the kind of
items that sit silently until they
are needed, generally during
inclement weather such as heavy rain or
snow. And if they are not up to the task
then, it could make the road ahead more
difficult to see and compromise a vehicle’s
safety. With this in mind, ACDelco offers a
line of windshield wipers that emphasize
reliability, innovative design and variety.
Generally sold as beam, conventional or
hybrid, windshield wipers represent a part
that should be regularly examined during
standard service inspections. To that point,
the 2024 Auto Care Association Fact Book
notes that, looking at replacement rates,
nearly half of the vehicles on the road
six to 15 years old could be eligible to be
changed out.
ACDelco recommends
that wipers be inspected
at least every six months
and be replaced in the event
of streaking or chattering, in which the
blade skips across the windshield. Beam,
conventional and hybrid parts are sold
across ACDelco’s OE/Gold/Silver tiers. OE
wiper blades feature a high-quality rubber
and special coating that help minimize
the friction on the glass. They also are
tested and validated to specific vehicle
applications over some 500,000 cycles.
Gold wipers cover nearly all GM vehicles
and 90 percent of other makes. Beam
wipers are the flagship, with their sleek,
modern look, a single contact point, an
airfoil blade that works to reduce wind
lift and a one-piece structure which helps
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To learn more about
ACDelco’s line of
windshield wipers,
scan the QR code.
resist snow and
ice clogging.
Special Beam
Professional
wipers don’t require
adaptors, making
them easier to install
on non-GM vehicles.
Hybrid wipers feature
a high-strength
polymer shell that
protects the blade from
the elements, and most
fit the 9x3 mm and 9x4
mm hook and side-lock
arm types.
With an attractive price
point, ACDelco Silver
blades display the
conventional, horizontal
design, and cover more
than 80 percent of U.S.
vehicles in operation.
These wipers feature
a stainless-steel
vertebra, a vented
primary lever for an
improved high-speed
performance and a
crimped joint design
for reduced lateral
movement.
n
Improving
the View
ACDelco windshield wipers
are designed for optimal
performance,
but they can be
affected by a variety of factors. A
recent Service Information bulletin
(#24-NA-164) examines the steps
owners and the technicians who
service their vehicles should follow
to get the most out of wipers.
Streaking is the most notable
indicator of wiper malfunction, but it
may not mean they are worn. Other
issues affecting wiper performance
include debris buildup on the blades
or the windshield, tears and nicks
in the rubber, or nonuniform edges.
Performing a quality diagnosis could
help determine whether a wiper is
being compromised.
Thoroughly clear the windshield of
anything in the wiper’s path, including
stickers or decals, cracks or nicks, or
tree sap or pollen. Remove each blade
from the windshield to clean it with
a lint-free cloth saturated in washer
solvent. Also, clean the glass before
replacing the blades. If a concern
disappears when the blades are
reattached, they don’t need to
be replaced.
Environmental conditions can
also play a role in a wiper’s
effectiveness.
Extremely dusty
or dirty areas can wear down the
rubber on blades, as can sand and salt
deposited on wintry roads. Owners
should avoid using the wiper blades
to clear ice on the windshield and rely
instead on the vehicle’s defrosters
or ice scrapers. When using ice
scrapers, it’s important to be
parallel with the wiper blades
so as not to scrape them and
tear the rubber.
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The 2025 GMC Terrain
,
the latest addition to the refreshed GMC
SUV family, boasts a unique design that
embodies the iconic GMC design language.
With a more robust and athletic stance
that shares design cues with its truck
stablemates, the Terrain exudes a fresh and
distinctive attitude.
The Terrain enhancements go beyond the
design by offering a wealth of standard
technology and equipment for the compact
SUV. The 2025 model year launched with
the Elevation trim, and the AT4 and Denali
trims will join for the 2026 model year.
Stay Informed
The Next Generation Terrain Elevation
is packed with standard and available
technology across all three trims, keeping
you connected and in control. This includes:
Q
Autosense power liftgate
Q
15-inch-diagonal Premium GMC
Infotainment System,
1
which can
simultaneously provide a view of up
to three applications, showcasing key
information on its screen
Q
11-inch diagonal Driver Information
Center
Q
Google built-in and Google Assistant
2
functionality, with which drivers can
issue voice commands, reply to text
messages, get directions through
Google Maps and control select vehicle
functions; some of these functions may
require a service plan/trial service plan
offered by OnStar that will have to be
purchased after the included trial period
expires
Q
Up to eight available camera views
3
with HD Surround Vision
3
and the Rear
Camera Mirror
3
— a first for the GMC
Terrain
Standard Comfort & Convenience features
include:
Q
5G Wi-Fi hotspot capability
4
Q
Remote start
Q
Heated steering wheel
Q
Heated front seats
Back in Black
For 2025, the Terrain Elevation more than
keeps up appearances with a number
of notable exterior touches. These start
up front with a unique upright grille and
distinctive LED headlamps (matched with
LED taillamps in back), 17-inch Grazen
Metallic machined aluminum wheels and an
available panoramic sunroof with a power
sunshade. There’s also the first two-tone
roof option on a GMC Terrain.
An available Elevation Black Edition boasts
exclusive design details, including 19-inch
High Gloss Black wheels, a darkened grille
and C-shaped surrounding bezel,
black mirror caps, roof-mounted side
rails, and accents and badging with red
GMC lettering.
PRODUCT SPOTLIGHT
2025 GMC Terrain Elevation
(shown with available features)
The 2025 GMC Terrain looks to
elevate the compact SUV segment
Each 2025 Terrain comes
standard with more than 15
safety and driver assistance
features
3
, including:
n
Enhanced Automatic
Emergency Braking
n
Front Pedestrian and
Bicyclist Braking
n
Intersection Automatic
Emergency Braking
n
Rear Cross Traffic Braking
n
Reverse Automatic Braking
n
Side Bicyclist Alert
n
Blind Zone Steering Assist
n
Adaptive Cruise Control
Continued on next page >
SAFETY
measures
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1. Functionality varies by model. Full functionality requires compatible Bluetooth
®
and smartphone, and USB connectivity for some
devices. 2. Google Assistant is not available in certain languages and countries. Requires internet connection. Service availability,
features and functionality are subject to limitations and vary by vehicle, device, location and active service plan. Device data
connection is required. Google Actions require account linking to use. Lock/unlock feature requires automatic locks. Remote
start/stop requires GM factory-installed and enabled remote start system. See onstar.com for details and limitations. Google,
Google Home, Android, and other related marks and logos are trademarks of Google LLC. 3. Safety or driver-assistance features
are no substitute for the driver’s responsibility to operate the vehicle in a safe manner. The driver should remain attentive to
traffic, surroundings and road conditions at all times. Visibility, weather and road conditions may affect feature performance. Read
the vehicle Owner’s Manual for more important feature limitations and information. 4. Service varies with conditions and location.
Requires active service plan and paid AT&T data plan. See onstar.com for details and limitations.
Highlights of the 2026 Terrain models include
standard heated and ventilated front seats and
heated rear outboard seats on the Denali and 17-inch
all-terrain tires and red front recovery hooks on the
rugged AT4 model.
Future Features
COMING
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PRODUCT SPOTLIGHT
Later this year,
GMC will launch
the 2026 model year Terrain AT4 and
Denali trims.
All-wheel-drive models come with Hill
Descent Control to handle challenging
roads or steep grades.
Standard content on the next generation
AT4 includes:
n
Selectable AT4-exclusive Terrain Mode
Q
Lifted ride height
Q
Metal underbody protection shield
Q
Animated headlamps and taillamps
Q
Red front recovery hooks
Q
17-inch all-terrain tires
Q
Trailer hitch
Denali sets a new standard on advanced
technologies, extraordinary craftsmanship
and unimpeachable luxury. Standard
features include:
n
Heated front and rear outboard seats
n
Animated headlamps and taillamps
n
19-inch wheels (20-inch wheels
available)
n
Unique Smart Frequency Dampers
for improved ride comfort and
performance
Q
Trailer hitch
Ready to Perform
The new Terrains are powered by a robust
1.5L turbocharged engine that delivers
an impressive 175 horsepower and 184
lb-ft (FWD)/203 lb-ft (AWD) of torque.
On front-wheel-drive vehicles, there’s a
continuously variable transmission; on all-
wheel-drive models, the Terrain Elevation
comes with an eight-speed automatic
transmission.
n
Soon
2026 GMC Terrain Denali
(shown with available features)
2026 GMC Terrain AT4
(shown with available features)
2025 GMC Terrain Elevation
(shown with available features)
Scan this QR code to learn more and keep
up to date on the 2025 and 2026 Terrain,
or visit
gmc.com/suvs/terrain.
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ACDELCO
A Ready
New
Resource
Courses
Diesel-Engine Performance 3: Fuel Systems
Course: SDE0303WB
This course covers the diesel-engine fuel supply,
including fuel supply types, components, fuel
conditioning and operation. It also examines
diesel-engine fuel-injection types and describes
fuel-return components and fuel-system testing.
Hybrid Electric Vehicle Collision Protocols
Course: SAP6001WB
This course provides an overview of the collision
protocols for Hybrid/Electric Vehicles (EVs) and
their importance. Upon completing this course, the
technician will be able to recall high-voltage safety
precautions, key elements of high-voltage system
inspection and the steps for high-voltage vehicle
inspection. Technicians will also be able to describe
high-voltage collision-repair best practices.
Braking Systems: EV Applications
Course: SBK1501WB
This course is for the non-Electric Vehicle (EV)
technician and answers what is similar and what
is different within the EV braking systems when
compared to conventional braking systems. Also
covered in this course will be the components,
characteristics and operation of regenerative
braking, including One-Pedal Driving and Regen on
Demand.
High-Voltage Battery Handling and Shipment
Course: SAP6101WB
This course provides an overview of the high-
voltage battery handling and shipment
protocols and their importance. Upon
completing this course, the technician
will be able to recall high-voltage
battery handling, the steps in preparing
a high-voltage battery for shipment,
and the high-voltage battery shipment
protocols.
Last issue, we
detailed many
of the ACDelco
training courses
debuting in 2025.
Here are a few
more web-based
classes that are
new for this year:
ACDelco training is a rich and complex
blend of service topics,
delivery methods,
technology and locations – and sometimes
it can be difficult to get your arms around.
There is a valuable resource designed to
bring all these aspects together in making
it easier to navigate the coursework
necessary to improve one’s knowledge
and skills.
The 2025 ACDelco Training Course
Catalog outlines the curriculum available to
personnel, and how they can access these
classes. It breaks down
the material by subject/
area of discipline, provides
a recommended path of
training and offers additional
courses that may be of
interest.
It also explains the benefits
of the online Learning
Management System, which
allows learners to enroll
in courses, tracks their
progress, and shows how
to navigate the site. The
catalog also examines the different ways
in which one can take training, whether
it be online or in-person, and the various
advantages that come from each. There’s
also a timeline that details
the development of the
ACDelco brand through the
20th and 21st centuries.
“ACDelco Training is
committed to providing
aftermarket repair facilities
with relevant and up-to-
date training covering
today’s advanced vehicle
technologies,” says John
Latner, Manager, ACDelco
Technical Training. “Our
training program provides
a multitude of delivery methods covering
numerous automotive skill areas. [And
learners can] check out our free training
offerings under the Test Drive link on
acdelcotraining.com
.”
n
ACDelco Course Catalog captures
key training information
Scan this QR code to access the 2025 ACDelco Training Course Catalog.
The 2025
ACDelco Training
Course Catalog
breaks down
the material by
subject/area of
discipline, provides a
recommended path
of training and offers
additional courses
that may be of
interest.
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Calibration Verification Procedure
GDS 2 Path
TIPS
Identify issues caused by
non-GM ECM calibrations
!
The advantages of
using General
Motors parts and following GM protocols
have been well-documented, but what
about the negatives when not following
GM specifications?
Case in point: GM has identified a growing
number of engine and transmission
failures due to the installation of non-
GM Electronic Control Module (ECM)
calibrations, in which software settings are
changed to modify engine performance.
When such an alteration with a non-GM
calibration takes place, the vehicle’s
powertrain and driveline components are
subjected to unknown stresses not tested
by GM. Also, such calibrations often don’t
meet the same emission standards as GM-
issued calibrations.
The good news is there are procedures in
place to identify non-GM ECM calibrations
through the use of the Tech 2 and GDS 2
diagnostic tools.
n
1.
Connect the Tech 2 to the vehicle.
2.
Go to Diagnostics.
3.
Select Powertrain, then Engine.
4.
Select Engine Control Module
or PCM.
5.
Select Module ID Information or
I/M Information System, if the
former selection isn’t available.
If I/M Information System is
selected, it may be necessary
to select Vehicle Information to
display the calibration data.
6.
Take a digital picture (or pictures)
of the Tech 2 Vehicle Information
screen showing the VIN, Engine
Calibration ID and Verification
Number. Save it in a JPEG format.
To retrieve the Engine Calibration
ID and Verification Number using the
Tech 2 tool, follow these steps:
1.
Disconnect the Tech 2 and update
it with latest software.
2.
Turn off the ignition for 90
seconds.
3.
Connect the Tech 2 to the vehicle,
turn on the ignition and build
the vehicle to display the Engine
Calibration ID and Verification
Number.
4.
If the Tech 2 screen still doesn’t
display the information, turn off
the ignition for 90 seconds before
turning it on again.
If the Tech 2 displays zeroes for
the Verification Numbers, perform
these steps:
1.
Turn off the ignition.
2.
Connect the Multiple Diagnostic
Interface (MDI) to the Data Link
Connector (DLC) of the vehicle.
3.
Then, connect the MDI to a PC or
laptop that has been downloaded
with Techline Connect and the
GDS 2 application.
4.
Select GDS 2 on the PC or laptop.
5.
Select the Diagnostics icon.
6.
Select the serial number of the
MDI being used.
7.
Select Enter icon, then Module
Diagnostics, then Engine Control
Module.
8.
If prompted, select Engine ID.
9.
Select Identification Information.
10. Select Calibration History to
display items such as the VIN,
stored calibration events and
part-number and verification-
number history.
11. Select Create Report, print it
and create a JPEG file.
To retrieve calibration information
using the GDS 2 tool, follow these
steps:
1.
Go to the Techline Connect
home page.
2.
Under Support, select SPS Info.
3.
Enter the VIN.
4.
Select Get Cal ID.
Following this, there is a calibration verification procedure to undertake whether
you are using a Tech 2 or GDS 2 tool:
5.
Select ECM Engine Control Module
— Programming from the Controller
drop-down menu, then select Next.
6.
Select Complete History to
access the GM Vehicle Calibration
Information screen, which displays
all GM-Approved Calibrations and
Verification Numbers.
If any of the acquired IDs and Calibration Numbers don’t match those listed on
the GM Vehicle Calibration Information screen, then non-GM calibrations may be
present. To ensure that these aren’t impacting powertrain concerns, the documented
information (in the form of JPEG files) should be sent to TACCVN@gm.com.
For more information on this
subject, access SI Bulletin
#09-06-04-026Z.
FIRMLY CONTROL
in
Tech 2 Path
Identify issues caused by
non-GM ECM calibrations
FIRMLY CONTROL
16
SPRING
2025
|
SERVICE
INSIGHTS
TIPS
Some full-size GM truck customers
(2019-2025 model years) may have
been getting two specific warning
messages — Check Trailer Wiring and
Service Trailer Brake — on the Driver
Information Center (DIC). In addition,
technicians may find DTC C1114 set on
vehicles equipped with an Integrated
Trailer Brake Controller.
This condition may be due to inability
of the 7-way trailer connector to
properly engage with a truck’s
socket, leading to open circuits.
Several manufacturers make these
connectors and don’t always comply
with SAE-standard specifications.
Because connections aren’t always
strong, the Trailer Brake Control
Module, which constantly monitors
the vehicle and trailer circuits/
components, can generate a “Check
Trailer Wiring” message on the
DIC. Deformation and excessive
wear of the terminals on a truck’s
7-way socket also will lead to a poor
connection.
GM Engineering recommends the
use of Pollak Heavy Duty 7-Way
Connector Plugs. Pollak is the OEM of
the truck’s socket, and, by using the
recommended plugs, this ensures a
proper fit.
If a truck’s connector socket
terminals are deformed, have
excessive wear or the door/cover
does not hold the trailer connector
plug securely, it will be necessary to
replace the socket with an updated
part (GM Part #84056018).
Other tips are to inspect and clean
the ground-wire connection on your
plug, make sure all wires inside the
connector are clean and securely
fastened, and, if the trailer has an
electrical junction box, it’s clean and
securely fastened.
n
STAY CONNECTED
Trailer
connector,
socket issues
may lead to DIC
messages
The Correction
!
For more information, please review
SI Bulletin #21-NA-155.
The Cause
The Issue