Bulletin No.: PIC6485D

Service Bulletin

Date: October, 2025

PRELIMINARY INFORMATION
Subject:

Diagnostic Tip - Noise or Vibration with A/C Compressor on

Brand:

Model:

Model Year:
from

Cadillac

LYRIQ

VIN:
to

2023-2026

from
All

Engine:

Transmission:

to
All

All

All

Involved Region or Country

North America

Additional Options (RPO)

RWL - CHASSIS DRIVE LINE-REAR WHEEL DRIVE (RWD)

Condition

A noise or vibration maybe noticed while the A/C Compressor is running.

Cause

Compressor upper mount twisted during attachment of the upper mount to the
compressor.

Correction

6236078

View from top side front of A/C compressor.
1. Front PEC Rail

Copyright 2025 General Motors. All Rights Reserved.

Page 2

October, 2025

Bulletin No.: PIC6485D

6236079

This is a View from the front of the A/C Compressor/Vehicle. If the gap between the upper Compressor mount to the
front PEC rail is not even across the width of the part, then the bracket has twisted when it was installed and can
cause NVH issues. If it has twisted, then the gap will be less on the passenger side of the part versus the driver's
side.

6236080

View from top side rear of A/C Compressor.
1. Loosen the through bolt that secures the compressor to the upper mount bracket enough that the bracket can
rotate back to a horizontal position.

Bulletin No.: PIC6485D

October, 2025

Page 3

6236081

View from top side front of the A/C Compressor.
Once the bracket is parallel to the ground and the PEC rail again, slide a shim (6.5 mm thick) or a screw driver
between the PEC rail and the bottom of the bracket to ensure the bracket does not twist again during re-torquing of
the bolt.
Torque through bolt to 30 nm + 45 to 60 degrees.

6236084

View from bottom side rear of A/C compressor.

Page 4

October, 2025

Bulletin No.: PIC6485D

After the fastener from the compressor to top mount bracket has been re-torqued, inspect the condition of the 2
lower mounts. The upper bracket (purple) and the lower bracket (cyan) of the lower mount system should be parallel
to each other.

6236086

View from bottom side rear of A/C compressor.
With the compressor in static load position, there should be no contact between the rubber isolator (snubbers) and
adjacent metal washers.

Warranty Information
For vehicles repaired under the Bumper-to-Bumper coverage (Canada Base Warranty coverage), use the following
labor operation. Reference the Applicable Warranties section of Investigate Vehicle History (IVH) for coverage information.
Labor
Operation
5080358

Description

Labor Time

Inspect and Align
High Voltage A/C
Compressor Mounts

1.5 Hrs.

*This is a unique Labor Operation for Bulletin use only.

Version

5

Modified

01/06/2023 - Created on.
06/14/2024 - Added 2024 model year.
09/13/2024 - Added RPO RWL.
01/29/2025 - Added 2025 Model Year.
10/17/2025 - Added 2026 Model Year

Bulletin No.: PIC6485D

October, 2025

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.

Page 5

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