18NA121

Bulletin No.:
Service Bulletin
Date:
18-NA-121
March, 2019
TECHNICAL
Subject:
Malfunction Indicator Lamp (MIL) Illuminated, 1st Gear and/or Reverse Only with No
Upshift, Vehicle Will Not Go Above 40 km/h (25 mph), 1-2 Shifts Feels Like a Momentary
Tie Up, DTC P2731 Set
This Bulletin replaces PIP5556. Please discard PIP5556.
Brand:
Buick
Model:
Regal
Model Year:
VIN:
from
to
2018
2018
2018
2018
from
to
Engine:
Equipped with
9-Speed
Automatic
Transmission
(RPOs M3D,
M3E,
M3T, M3V)
Cruze
Chevrolet
Equinox
Malibu
Transmission:
Traverse
Involved Region or Country
North America and N.A. Export Regions
Condition
Some customers may comment on one or more of the following conditions:
• Malfunction indicator lamp (MIL) illuminated.
• 1st gear and/or reverse only with no upshift.
• Vehicle won’t go above 40 km/h (25 mph).
• 1-2 shifts feels like a momentary tie up.
Some technicians may find the following DTC set in the TCM:
• P2731 – Transmission Control Solenoid Valve 6 Performance set in history
Cause
This condition may be caused by a software anomaly.
Correction
Replace the control valve body spacer plate and update the transmission control module
with the latest software available.
Service Procedure
Note: 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.
Refer to Control Valve Body Replacement and
Transmission Control Module: Programming and Setup
in SI.
Copyright 2019 General Motors LLC. All Rights Reserved.
Parts Information
Causal
Part
X
Description
PLATE ASM, C/
VLV BODY
SPCR (KIT)
Part
Number
24293402
(Regal,
Cruze,
Malibu,
Equinox)
24293403
(Traverse)
Qty
1
Page 2
March, 2019
Bulletin No.: 18-NA-121
Warranty Information
For vehicles repaired under the Powertrain coverage,
use the following labor operation. Reference the
Applicable Warranties section of Investigate Vehicle
History (IVH) for coverage information.
Labor
Operation
8480718*
Description
Labor Time
Valve Body Spacer Plate
Replacement and
Transmission Control
Module Reprogramming
with SPS
4.0 hrs
(Regal,
Cruze,
Malibu,
Equinox)
12.4 hrs
(Traverse)
*This is a unique Labor Operation for Bulletin use only.
Version
4
Modified
Released April 18, 2018
June 18, 2018 – Added the Regal model and updated the Parts Information.
October 3, 2018 – Updated the Labor Time under Warranty Information.
March 11, 2019 – Added RPO M3T to Transmission column in Models section and
updated the stable battery voltage during programming statement.
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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