BENDIX TCH-013-013 User Manual

Technical Bulletin

Bulletin No: TCH-013-013 Effective Date: 10/27/06 Cancels: N/A Page: 1 of 2

Subject: Bendix

Bendix ABS systems use sensors to monitor the vehicle's motion. For basic ABS braking and/or traction
functions, the Electronic Control Unit (ECU) uses the wheel speed sensors to detect wheel-slip conditions and
intervenes as needed.

In addition, Bendix advanced ABS ECUs, for example the Bendix® EC-60™ Advanced ABS with ESP® stability,
monitor the wheel speed sensors, steering wheel position, brake demand, vehicle load, and yaw rate/lateral
acceleration sensors to reduce the risk of rollovers, jackknifi ng and other loss of control.

ECU CONFIGURATION

Unlike previous generations of ECUs, Bendix® EC-60™ Advanced
ECUs are vehicle-specifi c and are individually confi gured. Bendix
and the original equipment manufacturer work together to specifi cally
customize the stability system for the individual vehicle confi guration
and its sensors. As a result, the vehicle's VIN number is required
when ordering a replacement ECU to ensure the same confi guration
is preset. See the Service Data sheet (SD-13-4869) for more
information.

SENSOR CALIBRATION

Since advanced ABS ECUs are individually customized based on
expected sensor locations and orientations, an out-of-calibration
sensor, or incorrectly positioned sensor, may lead to unwanted
and/or unneeded stability interventions, which can result in incidents
leading to loss of vehicle control.

A list of examples below show many vehicle maintenance
procedures that need to include Advanced ABS sensor recalibration.
Bendix® ACom® PC diagnostic software (version 5.3 or higher) is
used to recalibrate the sensors.

1. Steering Angle Sensor Examples.
The Steering Angle Sensor must be recalibrated as part of:

®

Advanced ABS Systems: Repair and Calibration

™

Bendix EC-60
Advanced ABS Controller

A Bendix WS-24™ Wheel speed sensor.
B Bendix SAS-60™ Steering Angle Sensor

(mounted to the steering column).

C Bendix YAS-60™ Yaw Rate/Lateral Acceleration

Sensor (typically mounted to a cross-member
near the back of the vehicle cab).

D Brake Demand Sensor (installed in the primary

and secondary delivery circuits), also used
as a Load Sensor (typically installed in the
suspension air bag).

A

B

• Steering wheel replacement (see Caution below.)

• Steering angle sensor replacement

• Any maintenance that involves opening the connector hub from
the steering angle sensor to the column

• Any maintenance or repair work on the steering linkage, steering
gear or other related mechanism

• Wheel alignment or wheel track adjustment

• Accident repairs where damage to the steering angle sensor
or assembly, or any part of the steering system may have
occurred

CAUTION: When replacing a steering wheel, use only OEM-approved
steering wheels. Take care not to damage the Steering Angle Sensor or
interfere with its operation during installation.

TYPICAL
ADVANCED ABS
COMPONENTS

continued over ...

C

D

Bulletin No: TCH-013-013 Effective Date: 10/27/06 Cancels: N/A Page: 2 of 2

Subject: Bendix® Advanced ABS Systems: Repair and Calibration

2. Yaw Rate/Lateral Acceleration Sensor Examples.
The Lateral Acceleration Sensor must be recalibrated as part of:

• Replacement of the sensor

• Repairs after an accident that may have led to damage of the yaw rate/lateral acceleration sensor

• Reinstalling the sensor anytime it is removed from the vehicle

Note: It is important that the small hole at the bottom of the Bendix® Y AS-60™ yaw rate/lateral acceleration sensor
is always open to the atmosphere. For this reason, do not paint the YAS-60™. If it is necessary to paint near the
Y AS-60™, remove the sensor from the vehicle. When reinstalling the Y AS-60™ to the vehicle after any maintenance
or painting work that required its removal, always recalibrate it using Bendix ACom™ PC software (versions 5.3 or
higher).

TRUCK CHASSIS MODIFICATIONS

If the vehicle’s chassis components are altered (for example, a wheel base extension or reduction, tag axle
addition or removal, a major body change such as conversion of a tractor into a truck, or an axle, suspension, or
steering system component modifi cation) the basic ABS functionality may continue to be used, but advanced ABS
features, such as the Bendix® ESP® system, must be disabled. See the appropriate Service Data sheet for more
information.

Reference Service Data Sheets:

EC-60™ ABS/ATC/ESP Controllers (Advanced Models) . . . .SD-13-4869 (BW2429)

TABS-6™ Trailer ABS Module . . . . . . . . . . . . . . . . .SD-13-4767 (BW2469)

ACom® Diagnostics PC software. . . . . . . . . . . . . . . . . . . . . . . BW2329

(Free downloads available on www.mybendix.com)

ABS Repair and Diagnostics DVD . . . . . . . . . . . . . . . . . . . . . . BW2538

Visit the Literature Center on www.bendix.com for free downloads of Service Data
sheets or to order copies.

ESP® is a registered trademark of DaimlerChrysler and is used by Bendix Commercial Vehicle Systems LLC under license.

©2006 Bendix Commercial Vehicle Systems LLC 10/06. All Rights Reserved. Printed in U.S.A.