20-NA-182

Service Bulletin
Bulletin No.:
20-NA-182
Date:
June, 2023
TECHNICAL
Subject:
Brake Booster Pump Motor Runs at All Times Even After Ignition Turned Off - DTC
C0021 Set
This bulletin replaces PIT5719. Please discard PIT5719.
Brand:
Model:
Chevrolet
Silverado 4500HD,
5500HD, 6500HD
Model Year:
VIN:
from
to
from
to
2019
2022
-
-
Engine:
Transmission:
-
-
Involved Region or Country
North America
Condition
Some customers may comment that the brake booster pump motor runs at all times even
after the ignition is turned off.
The technician may find DTC C0021 (Brake Booster Performance) set in EBCM.
Cause
The brake pressure switch may stick open.
Copyright 2023 General Motors LLC. All Rights Reserved.
Page 2
June, 2023
Bulletin No.: 20-NA-182
Correction
4961493
Replace the Brake Master Cylinder Pressure Sensor (3) with new updated part number.
Service Procedure
Refer to Brake Master Cylinder Pressure Sensor
Replacement in the Service Manual.
Parts Information
Causal
Part
Description
Part
Number
Qty
X
Switch Asm.
Press
19407495
1
Bulletin No.: 20-NA-182
June, 2023
Page 3
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
2441460
Brake Master Cylinder Pressure Sensor Replacement
Use the Published Labor
Operations Time
Version
2
Modified
Released September 16, 2020
Revised June 22, 2023 - Add 2021 and 2022 to Model Year and Update Part Number
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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