20NA164 Service Bulletin/Repair Instructions

Bulletin No.:
Service Bulletin
Date:
20-NA-164

August, 2020
TECHNICAL

Subject:

Brand:
Cadillac
Wire Brushing Type Noise Heard from Brake Rotors

Model:
CT6
Model Year:

from
2019
Breakpoint:

to
2020
from
—
to
—
Engine:
Transmission:
Equipped

with 2.0L or

4.2L Engine

(RPOs

LSY, LTA)
—
Involved Region or Country
United States, Canada, Europe, Russia, Middle East, Israel, Japan, Cadillac Korea

(South Korea)
Additional Options (RPOs)
Equipped with BRAKE SYSTEM-HEAVY DUTY / BRAKE SYSTEM-POWER,

FRT & RR DISC, ABS, 19", HEAVY DUTY (RPOs J55, J6H)
Condition
Some customers may comment on a wire brushing type noise heard from the brake

rotors.
Cause
5543923
This condition may be caused by the brake pad wear sensor being loose and making

contact with the brake rotor, as shown in the picture above.

Correction
Copyright 2020 General Motors LLC. All Rights Reserved.
Add adhesive to the slot of the brake pad wear sensor at the interface of the brake pad

following the Service Procedure listed below.
Page 2
August, 2020
Service Procedure
Bulletin No.: 20-NA-164
Parts Information
1. Remove the front disc brake pad wear sensor.

Refer to Front Disc Brake Pad Wear Sensor

Replacement in SI.
3M products may be purchased through your local

distributor. Information about 3M product retailers in

your area may be obtained by calling 1-866-364-3577

(U.S. and Canada).

Part

Number
DP420

BLACK*
Description

3M(TM)

SCOTCHWELD(TM)

EPOXY

ADHESIVE

DP420,

BLACK, 50ML
Qty
1
Material

Allowance

$12.50 USD

(per vehicle)

$16.29

Canada (per

vehicle)
*There is enough material to do approximately 4 vehicles.

Store the remaining material for future use.
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.

5635059
2. Apply 3M DP240 BLACK, or equivalent, over the

spring clip in the slot of the pad wear sensor

starting between the two lines (1) and going

around the spring clip (2), as shown in the picture

above.

Note: Make sure that the adhesive is flush to the

surface within the slot.

Version
1
Modified
Released August 18, 2020
Labor

Operation
Description
Labor Time
2486108*
Applying Adhesive Over the

Spring Clip in the Slot of the

Pad Wear Sensor
0.3 hr
*This is a unique Labor Operation for bulletin use only.
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

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