17-NA-047

Bulletin No.: 17-NA-047
Date: Feb-2017
Subject:
EBCM Wheel Speed Sensor Diagnostic Aid for ABS Message - Click or Ratchet Noise - Service Traction
Message - Service Stabilitrak Message - Service Steering Message
This Bulletin replaces PIC5428G. Please discard PIC5428G.
Brand:
Model:
Model Year:
VIN:
from
to
from
Engine:
Transmission:
to
Buick
Enclave
2008
2017
All
All
Buick
LaCrosse
2010
2016
All
All
Buick
Regal
2011
2017
All
All
Buick
Verano
2012
2017
All
All
(Front Wheel
Drive Only)
Cadillac
ATS
2013
2014
All
All
Cadillac
CTS
2008
2014
All
All
Cadillac
SRX
2010
2016
All
All
Cadillac
XTS
2013
2017
All
All
Chevrolet
Camaro
2010
2015
All
All
Chevrolet
Colorado
2009
2012
All
All
Chevrolet
Cruze
2011
2015
All
All
Chevrolet
Volt
2011
2017
All
All
Chevrolet
Equinox
2010
2017
All
All
Chevrolet
Corvette
2014
2017
All
All
Impala (VIN 1)
1
Chevrolet
Malibu Limited
2013
2016
All
All
Chevrolet
Traverse
2009
2017
All
All
GMC
Canyon
2009
2012
All
All
GMC
Acadia Limited
2007
2017
All
All
GMC
Terrain
2010
2017
All
All
Saturn
Outlook
2007
2010
All
All
Involved Region or Country
North America and N.A. Export Regions
Condition
Some customers may comment on any of the following conditions:
•
The ABS, Service Traction Control System, and/or Service Stabilitrak telltale lights are on. During initial
scan for EBCM module diagnostic codes you may find one or more of the following DTCs: C0035C0050 with specifically symptom bytes 18, 5A, 0F.
Note: For vehicles equipped with Electric Power Steering RPO NJ2 only - Operator may also notice a
Service Steering Message displaying in the Driver Information Center (DIC) and will experience
heavier steering feel at low speed or static steering maneuvers when this happens. This will be
accompanied with the Power Steering Control Module setting DTC U0415. This is a normal
default action with the loss of a Wheel Speed Sensor signal. If DTC U0415 remains after
removal of the Wheel Speed Sensor debris, refer to published diagnostics.
•
A brief and intermittent noise, click, ratchet, grind, or ABS pump motor noises typically heard from the
inside of the vehicle at parking lot speeds.
•
A flashing Traction Control or Stabilitrak telltale at low speeds.
Note: The latter two conditions correspond with no reported EBCM / ABS / Stability DTCs set current
or history.
Cause
These conditions may be caused by single or multiple pieces of ferrous metallic debris stuck to the wheel
speed sensor magnetic encoder ring.
Correction
Inspect and clean debris from the Encoder Ring.
Bearing Information
Note: THIS INFORMATION IS NOT APPLICABLE TO CAPPED WHEEL BEARINGS.
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(1.) Capped Wheel Bearing
(1.) Wheel Speed Sensor
Magnetic Encoder Ring - North and South Poles are shown
New Bearing Design.
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(1.) Magnetic Encoder Ring
Some new model vehicles today have begun to use a different type of wheel speed sensor encoder ring or tone wheel. Instead of a traditional mechanical type
tooth tone wheel, the wheel speed sensor tone wheel is now made of a magnetized nitrile rubber ring, typically brown in color. This magnetic encoder consists of
multiple North and South pole pairs surrounding the outer circumference. When this magnetic encoder ring rotates and passes by the wheel speed sensor
head; it generates a sign wave in the wheel speed sensor. The wheel speed sensor converts an analog signal to a digital square wave, and typical digital signal
values switch between 7mA (Low) and 14mA (High) DC current.
Parts Information
No parts are needed for this concern.
Warranty Information
Labor Operation
Description
Vehicle(s) Involved
Labor Time
2480068*
Inspect and Clean Debris
From Front Wheel Speed
Sensor Encoder Ring (One
Side)
Camaro, Corvette, CTS VIN D (RWD), Colorado (RWD), Canyon (RWD)
0.4 hr
SRX, Volt
0.7 hr
ATS (AWD), CTS VIN A/D (AWD), Acadia, Enclave, Outlook, Traverse,
1.0 hr
Equinox, Terrain, Cruze, Verano
2480078*
Inspect and Clean Debris
From Rear Wheel Speed
Sensor Encoder Ring (One
Side)
LaCrosse, Regal
0.9 hr
Malibu
0.8 hr
Impala, XTS
1.6 hrs
Colorado (4WD), Canyon (4WD)
1.9 hrs
Acadia (FWD), Enclave (FWD), Outlook (FWD), Traverse (FWD), SRX
(FWD), LaCrosse (FWD), Regal (FWD), Equinox (FWD), Terrain (FWD),
0.4 hr
Malibu, Impala, XTS (FWD)
Camaro, Corvette, CTS VIN D, Equinox (AWD), Terrain (AWD)
0.9 hr
SRX (AWD), ATS, CTS VIN A
1.1 hrs
4
LaCrosse (AWD), Regal (AWD)
2.1 hrs
Acadia (AWD), Enclave (AWD), Outlook (AWD), Traverse (AWD)
1.0 hr
Volt
0.8 hr
Cruze, Verano
0.6 hr
XTS (AWD)
1.4 hrs
*This is a unique Labor Operation number for Bulletin use only.
Service Procedure
Below inspection and cleaning procedure is supporting information to the SI wheel speed sensor diagnostic mechanical fault table. In most cases the DTCs
C0035-C0050 with symptom bytes 18, 5A, 0F can be repaired by removing and/or cleaning any accumulated debris on the magnetic encoder ring; which is
located on the inboard side of the bearing hub.
Important: Most repairs can be performed without any replacement of the bearing hub assembly or wheel speed sensor.
Important: For 2013-14 Buick Lacrosse, 2013-14 Buick Regal, 2014 Chevrolet Impala E, or 2013-14 Chevrolet Malibu, If the wheel bearing encoder
ring is damaged, replace the wheel bearing and follow Bulletin 16-NA-348.
Caution: Take care not to damage the bearing outer seal when brushing and/or cleaning the magnetic encoder debris.
Do not use any type of magnetic tool to remove the debris from the bearing magnetic encoder; an external magnet can damage the encoder.
BEFORE CLEANING
(1.) Sample Debris
1.
Based on the specific EBCM module Wheel Speed Sensor DTC code; inspect the appropriate corner magnetic encoder ring for possible debris.
- C0035 Left Front Corner
- C0040 Right Front Corner
- C0045 Left Rear Corner
- C0050 Right Rear Corner
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2.
If debris is found, perform the following cleaning recommendations.
Important: To properly clean the magnetic encoder ring, some applications may require removal of the bearing/hub assembly. Refer to the specific
Wheel Bearing and Hub Replacement procedure in SI.
2.1. Gently using a dry nylon soft bristle brush, remove the foreign debris off the magnetic encoder ring. If debris was removed, proceed to step 3.
2.2. If debris still remains, wash the encoder ring using a mild soap detergent and wipe dry.
Important: For 2013-14 Buick Lacrosse, 2013-14 Buick Regal, 2014 Chevrolet Impala E, or 2013-14 Chevrolet Malibu add wheel bearing deflector. Refer to
Bulletin 16-NA-348 for part number information.
AFTER CLEANING
1.
Connect a scan tool to the vehicle. Turn ON the ignition. Clear the DTCs.
2.
Perform vehicle diagnostic repair verification procedure for DTC: C0035-C0050. Refer to SI.
Version
1
Modified
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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