GLOBAL SAFETY FIELD INVESTIGATIONS
DCS4921
URGENT - DISTRIBUTE IMMEDIATELY
Date:

December 4, 2018

Subject: N182186880 - Service Update
Evaporator Core Leaks
Models: 2016-2018 Chevrolet Impala Equipped with 3.6L V-6 Engine (LFX)
To:

All General Motors Dealers

General Motors is releasing Service Update N182186880 today. The total
number of U.S. vehicles involved is approximately 4,472. Please see the
attached bulletin for details.
Global Warranty Management (GWM)
The Investigate Vehicle History (IVH) screen in the GWM system will be updated
December 5, 2018. Please hold all warranty transactions until IVH has been updated.
END OF MESSAGE
GLOBAL SAFETY FIELD INVESTIGATIONS

Service Update
N182186880 Evaporator Core Leaks
Release Date:
Attention:

December 2018

Revision:

00

This service update includes vehicles in dealer inventory and customer vehicles that return to the
dealership for any reason. This bulletin will expire at the end of the involved vehicle’s New Vehicle Limited
Warranty period.

Make
Chevrolet

Model
Impala

Model Year
From
To
2016
2018

RPO
LFX

Description
3.6L V-6 Engine

Involved vehicles are marked “open” on the Investigate Vehicle History screen in GM Global Warranty Management
system. This site should always be checked to confirm vehicle involvement prior to beginning any required inspections
and/or repairs.
Condition
Correction

On some 2016-2018 model year Chevrolet Impala vehicles the evaporator core may leak due to
condensate collecting and freezing between the lower tanks.
Dealers should reprogram the HVAC System Control Module to control evaporator icing.

Parts
No parts are required for this repair.
Warranty Information
Labor
Operation
9104000
9104217

Description
HVAC System Control Module Reprogramming with SPS
Module Programming Not Required

Labor
Time
0.3*
0.2**

Trans.
Type
ZFAT
ZFAT

Net
Item
N/A
N/A

* To avoid warranty transaction rejections, the SPS Warranty Claim Code must be entered when submitting this
transaction. Note that if multiple modules are reprogrammed, all claim codes must be entered with a comma separating
each code.
** SPS Warranty Claim Code is NOT required when submitting this transaction.
Service Procedure
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. When required install a GM Authorized Programming Support Tool to maintain system
voltage. Refer https://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.

Caution: If the Same Calibration/Software Warning is noted on the SPS Controller screen, do NOT attempt to program
the module. No further action is required. Refer to the Warranty section of the bulletin and use labor operation code
9104217, Module Programming Not Required.
1.

Reprogram the HVAC system control module. Refer to HVAC System Control Module: Programming and Setup in
SI.

2.

Record SPS Warranty Claim Code on job card for warranty transaction submission.

Copyright 2018 General Motors. All Rights Reserved.

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Service Update
N182186880 Evaporator Core Leaks
Dealer Responsibility
Whenever a vehicle subject to this service update enters your vehicle inventory, or is in your facility for service in the
future, and the vehicle is still covered under the New Vehicle Limited Warranty, you must take the steps necessary to be
sure the service update correction has been made before selling or releasing the vehicle.
All new, used, GM Certified Used, courtesy transportation vehicles, dealer shuttle vehicles, etc. in dealers' possession
and subject to this bulletin must be held and inspected/repaired per the service procedure of this bulletin before customers
take possession of these vehicles. Involved vehicles must be held and not delivered to customers, dealer-traded,
released to auction, used for demonstration, or any other purpose.
All GM Certified Used vehicles currently in the dealers’ inventory within the Certified Pre-Owned Inventory System
(CPOIS) will be de-certified and must be held and remedied per the service procedure in this bulletin. Upon submitting
an accepted/paid warranty transaction in the Global Warranty Management (GWM) system, the vehicle can be re-certified
for sale within the CPOIS system, or once again be used in the CTP program.

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 tools, equipment, 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 dealer for information on whether your
vehicle may benefit from the information.

We Support
Voluntary Technician
Certification

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