21-NA-283

Bulletin No.:
Service Bulletin
Date:
21-NA-283
August, 2023
TECHNICAL
Subject:
Service Front Suspension Lift System Message Displayed on Driver Information
Center (DIC), Noise from Suspension Pump – DTC C103C and/or C103E Symptom
64 Set
This bulletin replaces PIC6434A. Please discard PIC6434A.
Brand:
Model:
Chevrolet
Corvette
Model Year:
VIN:
from
to
from
to
2020
2023
All
All
Engine:
Transmission:
All
All
Involved Region or Country
North America, Europe, Middle East, Japan, Australia/New Zealand
Additional Options (RPO)
Front Suspension Lift System (RPO E60)
Condition
Some customers may comment that they have seen a Service Front Lift System
message displayed on the DIC in combination with an abnormally loud pump noise.
Technicians may find one or more of the following DTCs set:
• C103C: Left Front Strut Position Sensor Signal
• C103E: Left Front Strut Position Sensor Signal
• Symptom 64: Signal Plausibility Failure (This sub type is used for failures where the
control module detects a single input parameter is operating outside the plausible
range.)
Cause
An issue in the supplier manufacturing process on some lift pumps may cause this
condition over time.
Correction
Refer to the Service Procedure to verify the condition.
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.
1. Ensure DTC C103C or C103E SYM 64 is in
Current or History status on the vehicle.
Note: This bulletin does not apply if one of these DTCs
did not set.
2. Start vehicle and operate lift system using the
button on the center console with the windows
lowered.
3. Compare the pump noise to the two examples
below.
3.A.
If the sound is similar to the Suspect Pump,
replace the pump per SI procedures including a
hydraulic system bleed.
3.B.
If the sound is similar to the Acceptable Pump,
proceed with normal SI diagnosis for the DTC
which set on the vehicle.
Parts Information
Causal
Part
X
X
Copyright 2023 General Motors LLC. All Rights Reserved.
Description
Module, Frt Susp
Lvlg/Lifting Hyd
Pwr Pack
Module, Frt Susp
Lvlg/Lifting Hyd
Pwr Pack
Part
Number
Qty
84923536
1
85170579
1
Page 2
August, 2023
Bulletin No.: 21-NA-283
Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation
8020450
Description
Labor Time
Front Suspension Leveling/
Lifting Hydraulic Power Pack
Module Replacement
(Includes: Bleed hydraulic
system).
Use
Published
Labor
Operation
Time
Version
5
Modified
Released December 06, 2021
Revised January 28, 2022 – Added Suspension Pump Noise to Subject and Condition
section and added Additional SI Keywords.
Revised August 24, 2022 – Added the 2023 Model Year.
Revised September 28, 2022 – Updated Correction section information.
Revised August 14, 2023 – Updated Condition, Cause, Correction, Service Procedure,
Parts Information, and Warranty Information sections.
Additional SI Keywords: loud, noisy, pump, assembly,
PDI, rattle
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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