Bulletin No.: 24-NA-120

Service Bulletin

Date: June, 2024

INFORMATION
Subject:

Information on Malfunction Indicator Lamp (MIL) Illuminated - Multiple
DTCs Set

Brand:

Model:

Chevrolet

Silverado 1500 LD

GMC

Sierra 1500 Limited

Model Year:

VIN:

from

to

from

to

2023

2023

-

-

Engine:

Transmission:

3.0L (LZ0)

All

Involved Region or Country

North America, Europe, Middle East, Argentina (Mercosur), Brazil (Mercosur), Bolivia
(West), Chile (West), Colombia (West), Ecuador (West), Paraguay (West), Peru (West),
Uruguay (West), Cadillac Korea (South Korea), Philippines, Australia/New Zealand

Additional Options (RPOs)

Equipped with 3.0L Engine (RPO LZ0)

Release Date

What The Release Addresses

April 1, 2023 DTC’s

P0402 - Exhaust Gas Recirculation Valve Flow Excessive
P049C - Exhaust Gas Recirculation Valve 2 Excessive Flow
P054E - Idle Control - Fuel Quantity Lower Than Expected
P1089 - Fuel Rail Pressure Performance During Deceleration Fuel Cut-Off
P140C - Exhaust Gas Recirculation Valve Slow Response - Decreasing Flow
P149A - Engine Coolant Temperature Sensor 2 Not Plausible
P2203 - Nitrogen Oxides Sensor Circuit High
P22A1 - Nitrogen Oxides Sensor 2 Circuit High
P23AF - Nitrogen Oxides Sensor 3 Circuit High
P242B - Exhaust Gas Temperature Sensor 3 Performance
P2459 - Particulate Filter Regeneration Frequency P2635
P261F - Auxiliary Coolant Pump Stuck On — Internal Component Fault

August 1, 2023 DTC’s

P0300 - Engine Misfire Detected
P049D - Exhaust Gas Recirculation Valve Position Not Learned
P1C30 - Reductant Injector 2 Temperature Sensor and Exhaust Gas Temperature Sensor
Correlation
P20EE - Nitrogen Oxides Catalytic Converter Efficiency Below Threshold
P20FE - Nitrogen Oxides Sensor Performance - Sensing Element
P2203 - Nitrogen Oxides Sensor Circuit High
P22FB - Nitrogen Oxides Sensor Performance - Sensing Element
P22FE - Nitrogen Oxides Sensor 2 Performance - Sensing Element
P2C7A - Nitrogen Oxides Catalytic Converter 2 Efficiency Below Threshold
P2EAD - Reductant Injector 2 Performance - Low Reductant Consumption

Copyright 2024 General Motors. All Rights Reserved.

Page 2

June, 2024

Bulletin No.: 24-NA-120

December 1, 2023 DTC’s

Some customers may comment of a malfunction indicator lamp illuminated. The technician may find that the vehicle with the stop start issue above or that one of the following
DTCs are set:
P049D - Exhaust Gas Recirculation Valve Position Not Learned
P140C - Exhaust Gas Recirculation Valve Slow Response - Decreasing Flow
P2002 - Particulate Filter Low Efficiency
P2297 - Heated Oxygen Sensor Performance During Deceleration Fuel Cut-Off
P22FB - Nitrogen Oxides Sensor Performance - Sensing Element
P22FE - Nitrogen Oxides Sensor 2 Performance - Sensing Element
P2459 - Particulate Filter Regeneration Frequency

Cause

These condition(s) may be caused by a software anomaly.

Correction

Please check for any Engine Control Module (ECM) updates. If none are available, refer
to the proper procedures in SI.

Service Procedure

Parts Information

Important: Service agents must comply with all
International, Federal, State, Provincial, and/or
Local laws applicable to the activities it performs
under this bulletin, including but not limited to
handling, deploying, preparing, classifying,
packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict
between the procedures set forth in this bulletin
and the laws that apply to your dealership, you
must follow those applicable laws.

No parts are required for this repair.

Version

1

Modified

Released June 27, 2024

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.

WE SUPPORT VOLUNTARY
TECHNICIAN
CERTIFICATION