Bulletin No.: 21-NA-043

Service Bulletin

Date: November, 2024

INFORMATION
Subject:

Properly Maintaining Vehicles in Dealer Inventory

Brand:

Model:

Model Year:
from

BrightDrop
Buick
Cadillac
Chevrolet
GMC

Zevo 400

2024

Zevo 600

2023

GM
Passenger
Cars and
Light/Medium
Duty Trucks

2011

Involved Region or Country

VIN:
to

from

to

—

—

Engine/
Propulsion:

Transmission:

All

All

2024

2025

North America

Dealer Inventories
Important: Dealers are responsible for the storage and proper care of new vehicles held in dealer inventory or
customer vehicles in for Warranty or Recall repairs until they are delivered or returned to the customer. Extra care
and attention to detail should be taken to make sure vehicles that have spent longer times in dealer inventory are
properly delivered to the customer with no product issues (such as stall/no start issues due to improper battery
maintenance or vehicle vibration due to tire flat spotting). Damage or deterioration, resulting from improper storage,
is not to be covered by the New Vehicle Limited Warranty. For more information, refer to the New Vehicle Storage
section of the Service Policies and Procedures Manual.
Table of Contents
The following is a list of topics included in this bulletin:
• Battery Maintenance
• Underhood Inspection (ICE Vehicles)
• Tire Flat-Spotting
• Brakes
• Tire Pressure Monitoring System (TPMS)
• Protective Shipping Materials
• Checking/Cleaning Windshield Wipers/Window Glass
• Fuel/Lubricants/Oil Life Monitor
• Diesel Engine Special Care
• Storage Lot Practices/Vehicle Washing
• Field Action Bulletin and Pre-Delivery Inspection Completion

Battery Maintenance
12 Volt System
Leaving vehicles in Transport Mode while in inventory will extend the time between charge events. Refer to Power
Mode Description and Operation/Transport Mode (If Equipped) in SI for information on turning this feature off and on.

Copyright 2024 General Motors. All Rights Reserved.

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November, 2024

Bulletin No.: 21-NA-043

Important: Starting model year 2023, Korean built vehicles can be left with Transport mode ON and will not inhibit
our ability to receive data from these vehicles.
U.S. Dealers
U.S. dealers are to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require
attention. The Report, located in the Dealer Maxis application on the GlobalConnect App Center, will conveniently
identify the specific vehicles in your dealer inventory that require a “Battery Charge” due to a low state of charge.
• It is recommended that dealers monitor the report only once per week.
• Vehicles on the report that require a Battery Charge should be charged using the “Diagnostic Charge” on the
GR8 or the “Diagnostic – Trolley” process with the Diagnostic Charge Battery Station (DCBS). For vehicles with
two batteries, each battery must be electrically isolated and charged individually, which will result in two
printouts.
Note: Vehicles with Stop/Start Auxiliary batteries must be charged separately from the main battery during the
period of dealer inventory storage. The Auxiliary battery is not connected in a manner that will allow both batteries to
be charged at the same time and must be charged individually, which will result in two printouts.
• The report will also identify vehicles that need to be started and moved as they remained dormant for an
extended period and are no longer transmitting battery state of health information to GM via Remote Vehicle
Diagnostics. These vehicles should be started and moved too so that GM can provide proper recommendations
to you on battery maintenance.
• After taking action on any particular vehicle noted on the Battery Maintenance Report, it may take up to 5 days
for the vehicle to be removed from the Report.
Canadian Dealers
Maintain battery charge on vehicles in dealer inventory per the following:
1. At vehicle delivery to the dealership (PDI), check condition and charge the battery using the GR-8 Tool
(EL-50313) or EL-52800 Diagnostic Charge Battery Station (DCBS) in the PDI mode. This step allows the
battery to be charged back up (topped off) at PDI (for 20 minutes or less) to make up for any loss of charge that
occurred during the vehicle transit time from assembly plant to the dealer. Allowing PDI Mode to enter TOP OFF
Mode automatically or manually selecting TOP OFF Mode at the screen prompt at the end of PDI Mode will
allow a complete charge of the battery and aid in preventing dead batteries in dealer inventory.
Note: Utilizing TOP OFF Mode after PDI Mode will allow for a complete battery charge during inventory storage and
to improve customer satisfaction after vehicle delivery.
2. Every 30 days in dealer inventory, check condition and charge the battery using the GR-8 Tool (EL-50313) or
the EL-52800 Diagnostic Charge Battery Station (DCBS) in the PDI mode. This step will allow the battery state
of charge to be maintained, which maximize over all battery life. Vehicle batteries that are in dealer inventory for
extended amounts of time without being maintained/charged will see a significant overall reduction in the
battery's service life.
3. At point of sale (just prior to delivering the vehicle to the customer), check condition and charge the battery
using the GR-8 Tool (EL-50313) or the EL-52800 Diagnostic Charge Battery Station (DCBS) in the PDI mode.
This step will ensure that the battery is fully charged for the best customer satisfaction possible.
4. On vehicles with two Batteries, each battery must be electrically isolated and charged individually, which will
result in two printouts.
Note: Vehicles with Stop/Start Auxiliary batteries must be charged separately from the main battery during the
period of dealer inventory storage. The Auxiliary battery is not connected in a manner that will allow both batteries to
be charged at the same time and must be charged individually, which will result in two printouts.
12 Volt Battery Replacement on Vehicles in Dealer Inventory (U.S. and Canadian Dealers)
For dealers who follow proper battery maintenance guidelines, defective batteries that fail to properly charge are
covered under the New Vehicle Warranty. Replacement must be supported by a “Replace Battery” decision from the
GR8 or DCBS, and a copy of the test result printout must be retained with the job card. Refer to Service Bulletin #
20-NA-132 for further details and claim submission requirements.
High Voltage Batteries
For Electric Vehicles (EVs), the High Voltage (HV) battery provides maintenance of electric vehicle’s 12V battery as
long as the HV battery is above 15% state of charge. Dealerships should ensure the HV battery system is kept
above this level to maintain support of the 12V battery.

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The High Voltage batteries should be fully charged to the factory pre-set charge level prior to completing the PDI.

Underhood Inspection (ICE Vehicles)
Inspect vehicles that have been sitting (especially for an extended period of time) for evidence of animal
nesting. Open the hood and check for/remove any organic debris (such as, dried grass, leaves, etc.)
• Locations - include top of engine, between valve cover and intake manifold, catalytic converters, and exhaust
manifold (any potential hot surface area).
• If this type of material contacts any hot exhaust/other components, melting or burning could result.

Tire Flat-Spotting
All tires, no matter the manufacturer, are susceptible to flat spotting if the vehicle sits on the dealership lot prior to
customer delivery and is not moved or driven for an extended period of time. Flat spots on the tires can cause
vibration concerns.
Vibration issues for flat spotting can develop between 30-45 days (depending on the tire design, parking surface and
weather conditions) and usually will be gone after allowing the tires to heat up after a few minutes of driving at
highway speeds on smooth surface roads.
Vibration issues that develop from allowing the vehicle to sit without being moved/driven for between 45-90 days
usually will be gone after allowing the tires to heat up after 10 minutes of driving at highway speeds on smooth
surface roads.
Vibration issues that develop from allowing the vehicle to sit without being moved/driven for more than 90 days may
become permanent and would require tire replacement to repair (which would not be considered a warrantable
item).
To attempt to minimize this concern, the following is recommended:
-

Tires should be inflated to 300 kPa (44 psi) for longer term storage in inventory. While higher tire pressures
during storage has not been proven to eliminate this concern, underinflation has been shown to contribute to its
severity, so higher pressure is preferred to lower pressure.

Tip: Tires on average lose 7 kPa (1 psi) every 30 days. Additionally there is a 7 kPa (1 psi) loss in pressure for
each 6°C (10°F) drop in air temperature. Example: A tire with 300 kPa (44 psi) at 16°C (60°F) would have 240
kPa (35 psi) after 6 months in inventory at −1°C (30°F) air temperature.
-

Vehicles should be moved every 30 days. If vehicles are allowed to sit more than 30 days at a time, more
noticeable or objectionable tire vibrations may be noted. Vibration issues that develop from allowing the vehicle
to sit without being moved/driven for more than 90 days may become permanent and would require tire
replacement to repair (which would not be considered a warrantable item).

Tip: U.S. dealers can monitor the Battery Maintenance Report located in the Dealer Maxis application on the GlobalConnect App Center to identify vehicles that have been sitting for greater than 30 days without an ignition cycle. The
report will conveniently list the specific vehicles in your dealer inventory that should be started and moved.
At the time of delivery, vehicle tire pressures MUST be reset to the values as outlined on the Tire Pressure
Placard in order to provide the customer with the proper ride and handling characteristics designed into the vehicle.
Important: If any tire vibration is noted during the PDI process before measuring tires on equipment such as the
RFE 13 Road Force® Elite Balancer, the vehicle MUST be driven a minimum of 24 km (15 mi) to ensure removal of
any flat spotting (The tendency to "flat spot" is less likely as the tire accumulates mileage).

Brakes
Extended outside storage with no vehicle movement may increase the opportunity for brake noise and/or pulsation
issues. Vehicle braking systems tend to be self-cleaning while vehicles are in use, preventing any build-up of
corrosion on the brake rotor surfaces. Therefore, vehicles in dealer inventory should be moved and brakes applied
several times every 30 days to prevent issues.
Tip: U.S. dealers can monitor the Battery Maintenance Report located in the Dealer Maxis application on the GlobalConnect App Center to easily identify vehicles that have been sitting for greater than 30 days that should be started
and moved to eliminate rust build up.

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Bulletin No.: 21-NA-043

Tire Pressure Monitoring System (TPMS)
The TPMS is learned at the assembly plant and should not need to be re-learned at customer delivery unless wheels
are replaced or rotated. Vehicles that have been in dealer inventory for extended amounts of time may have a TPMS
light on indicating proper tire pressure (air inflation) is required. Properly adjusting all tire air pressures to the recommended levels and driving the vehicle will turn the light off (refer to the Tire and Loading Information label on the
driver side door) - DO NOT re-learn the TPMS. Follow appropriate sections of SI in the event diagnosis of TPM Light
or “Service Tire Pressure Monitoring System” DIC Message is required at PDI or point of sale.

Protective Shipping Materials
Many GM vehicles come with protective coverings, foam blocks and other preventative measures applied before
vehicle shipping to aid in vehicles being delivered in the best possible condition.
The exterior protection foam block door and bumper protectors should be left in place up to the time of the customer
delivery except for vehicles on prominent display such as the showroom floor. These protective devices help to
minimize lot damage, reduce dealer expense and increase customer satisfaction.
General Motors has communized the use of door edge protection in order to reduce the chance of chips/scratches
on the doors of new vehicles. The protectors come in the form of a black foam block that adheres to the painted door
panel by a sheet of white, two-sided tape. This foam block is designed to protect not only the painted body panel, but
also any body cladding or moldings on the vehicle. The location of the door protection varies, depending on the
contours of the door or body cladding. The purpose of this protection is not only to protect the vehicle during transportation from the plant to the dealer, but also while the vehicle is either stored or displayed at the dealership. GM
recommends the door edge protection stay on the doors up until delivery to the customer. By leaving this
protection in place, the possibility of door chips, scratches or dents is virtually eliminated.

Checking/Cleaning Windshield Wipers/Window Glass
Wiper Blades
Vehicle windshield wipers are exposed to weathering elements as soon as a vehicle is produced. During extended
outdoor storage the wiper blades may not function as well due to the following factors:
• Dirt/debris/dried soap stuck on the blade surface
• Oxidation of the rubber blade
• The rubber blade may take a “permanent set” from non-use.
If necessary, the wiper blades can be cleaned with a lint free cloth or paper towel soaked with windshield washer
fluid (GM Optikleen recommended) or a mild detergent. You should see significant amounts of dirt being removed on
the cloth. Be sure to wash the windshield thoroughly when you clean the blades. Bugs, road grime, sap and a
buildup of car wash/wax treatments may additionally cause wiper streaking.
Important: Avoid getting windshield washer fluid on your hands. Wear rubber gloves or avoid direct contact with
washer fluid. NEVER use gasoline, kerosene, or petroleum based products to clean wiper blades.
Tip: DO NOT operate the wipers if the vehicle is extremely dirty with gritty or sandy materials, or twigs/sticks in the
cowl area. This type of debris dragged by the force of the wipers while dry may cause glass scratching.
Window Glass
The interior surfaces of the window glass may appear hazy (due to surface deposits) after a vehicle has sat in a
“closed-up” condition for an extended period of time. It is suggested that window washing during the PDI process be
performed with plain water. Washing by this method increases the amount of time that the windows will stay clean,
as cleaners generally leave a film that accelerates the deposition of new dirt.
ONLY if satisfactory results cannot be obtained (streaking), please use GM Vehicle Care Glass Cleaner (or equivalent) to clean heavier deposits.

Fuel/Lubricants/Oil-Life Monitor
Caution: Do not allow vehicles to run out of fuel during idle conditions. Allowing a vehicle to run out of fuel while
idling may cause damage to the fuel pump.

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Gasoline Fuel
As vehicles age while in inventory the potential for fueling issues increases. Gasoline powered vehicles should not
encounter any fuel related issues while being stored for up to one year. Vehicles should have fresh fuel added as
needed or if in stock for over one year.
Lubricants and Oil Life Monitor
As vehicles are kept in stock for longer periods of time, questions may be raised not only by the new car prep
personnel, but also by customers. Here are some suggestions as to proper business practices.
The Oil Life Monitor in new GM vehicles will count down as vehicles are started, moved and run for the purpose of
battery charging. If vehicles remain in stock for longer periods, what guidelines should you follow to answer
questions about the oil life monitor?
-

When the vehicle was assembled the oil life monitor begins counting down the useful life of the oil. If the Oil Life
percentage indicates below 90% of the oil life left before vehicle delivery and the vehicle is older than 7 months,
it is advised that the oil be changed before delivery to the customer (An alternative would be to offer the
customer a discount coupon good for a reduced cost oil change, to compensate for used up oil-life before
delivery).

Important: The Oil-Life Monitor should not be reset at the time of delivery unless the vehicle oil has been changed.
-

If the Oil Life Monitor indicates above 90% or the vehicle build date is within 6 months or newer, the vehicle may
be delivered without additional action. There is always some period of time that a vehicle is in dealer stock
before it is delivered, and that small drop in oil life is expected.

Important: If a vehicle remains in stock for 1 year or greater, you should change the vehicle engine oil.

Diesel Engine Special Care
Periodic Operation
Diesel powered vehicles should not be left stationary for more than 45 days. When the storage duration approaches
45 days, the vehicle should at least be started and idled until the engine reaches operating temperature. Ideally, the
vehicle should be driven for at least 1.6 km (1 mi) and then idled to operating temperature to prevent turbocharger
malfunction.
Fuel
Diesel powered vehicles should not have additional fuel added to the tank unless required. The assembly
plant fuels vehicles with a special blend of ultra low sulfur diesel extending its stability over marketplace diesel fuel.
Fuel readily available in the consumer market may have high levels of Biodiesel and likewise shorter storage
potential. If re-fueling is required, add only in 15 L (4 gallon) increments using winter blend fuels where appropriate.
Diesel Exhaust Fluid
Diesel Exhaust Fluid must be added (if not factory filled) at the time of Vehicle Pre-Delivery Inspection up to
9.46 liters (2.5 gallons). Make certain the GM provided nozzle, including internal vent tube, is used to ensure
proper feedback from the fill limit valve. DO NOT OVERFILL THE TANK. When the fluid first begins to overflow out
of the fill neck, the tank is full.
Battery State of Charge
Wherever possible, diesel-powered vehicles should have the batteries maintained with a battery charger as opposed
to running the vehicle for 30 minutes to conserve the factory fueling.

Storage Lot Practices/Vehicle Washing
While all damage and every situation cannot be accounted for, simple thoughtfulness and care should be your guide.
There are many opportunities for damage to the finish of vehicles. Please review the following good discussion
starters with porters and technicians:
• Simple winter season conditions can be a good source of damage for northern dealers. Sharp snow shovels
and ice scrapers can damage vehicles. Consider the use of plastic shovels (non-metal edged) for use in and
around vehicle storage lots and make sure snow removal tools are in good condition. Instruct dealership
personnel to be aware of potential damage when removing ice buildup from the vehicles.
• Keep bushes and shrubs trimmed back around vehicle storage lots. Sometimes, when space is at a premium,
every inch of a lot is utilized. Do not park vehicles near landscaping that, during a thunderstorm or winter storm,
may droop or move sufficiently to contact vehicles, causing finish damage.

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Bulletin No.: 21-NA-043

• Regularly maintain your dealership car wash. Worn components or improperly working mechanisms and valves
may damage or cause dulling of vehicle finishes. If your dealership hand washes and polishes vehicles for
delivery, reconfirm that personnel are dressed in proper clothing devoid of belt buckles, metal buttons/snaps,
wallet chains, etc.
• Vehicles on the front lot, visible by customers, should be kept clean and washed regularly for the sake of a nice
dealership appearance. Vehicles in off-site storage, or secured areas should be kept clean preferably by
touchless methods. Constant washing may create fine scratches or swirls in the paint on dark colored vehicles.
Lightly power washing with soap will remove any harmful accumulations of dirt, bird droppings, acidic leaves,
etc. without the risk of causing scratches.
Important: Some vehicles come from the factory with a matte paint finish. Matte finishes require special care while
washing to avoid damage to the paint. Refer to Bulletin# 23-NA-016 for additional information.

Field Action Bulletin and Pre-Delivery Inspection Completion
To ensure vehicles are delivered to customers with no product issues, review and complete any open field actions
using Investigate Vehicle History (IVH) and complete the pre-delivery inspection (PDI) BEFORE the vehicle is
delivered to the customer.
Version

6

Modified

Released February 25, 2021 – Corporate Service Bulletin Number 09-00-89-002R has
now become Global format Service Bulletin #21-NA-043. This update revises U.S.
policies regarding Battery Maintenance and Tire Flat Spotting.
Revised July 20, 2021 – Added the 2022 Model Year, removed obsolete Bulletin #
reference and added Bolt EV/EUV reference in Exception statement under 12 Volt
System.
Revised May 16, 2022 – Added the 2023 Model Year and updated information under
Dealer Inventories, U.S. Dealers under Battery Maintenance and High Voltage Batteries
sections.
Revised March 20, 2023 – Added the 2024 Model Year and updated applicable
information throughout the bulletin.
Revised April 30, 2024 – Added the 2025 Model Year.
Revised November 04, 2024 – Added BrightDrop models and Underhood Inspection (ICE
Vehicles) section.

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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