Navistar WorkStar Series, Operator'S Manual

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Operation
Stability Control Systems – Bendix® ESP
WARNING
Vehicles equipped with Stability Control have
reduced
effectiveness when pulling double
or triple trailers. Failure in understanding
this warning could result in property damage,
personal injury, or death.
WARNING
Stability Control systems are designed to
enhance overall vehicle stability by automatically
reducing vehicle speed under certain conditions.
Drivers operating a Stability Control equipped
vehicle should employ safe driving practices
and assume no additional driving risks. Failure
to follow this warning could result in property
damage, personal injury, or death.
CAUTION
Modification to vehicles equipped with ESP
require prior approval thru Navistar’s Tech
Services
# 1-(800)-336-4500. Unapproved
modifications may result in diminished stability
control performance.
The optional stability control system provides the core ABS
function as well as Automatic Traction Control (ATC) and roll
stability functions.
Core ABS Functions: The core ABS system reduces wheel
lockup to help drivers maintain steering control while braking.
Antilock Braking Systems (ABS) use wheel speed sensors,
ABS pressure modulator valves, and an Electronic Control
Unit (ECU) to control either four or six wheels of a vehicle.
ECUs optimize slip between the tire and the road surface by
monitoring individual wheel turning motion during braking.
Advanced Stability Functions: This function enhances
stability by sensing actual vehicle dynamics. ESP–equipped
vehicles add yaw control to the basic roll stability feature.
Vehicle Stability Control Speed Reduction: In the case of a
potential roll event, the stability system will remove the throttle
and quickly apply brake pressure to slow the vehicle combination
below the threshold.
Steering Angle Sensor: This sensor enables the advanced
stability system to capture the driver’s steering input and
intervene if a yaw correction is needed.
The sensor also
provides the earliest indication of an increase in lateral
acceleration that might cause a potential roll event. A steering
angle sensor provides a greater stability margin than a vehicle
that is not equipped with this sensor.
Brake Demand Sensors: The stability control system was
designed to supplement the driver’s actions.
By directly
measuring driver brake demand, the system can transition
seamlessly between driver-intended and system-intended
braking pressure. For example, if in a certain maneuver, the
system calculates 40 psi (276 kPa) is needed and the driver
is only applying 20 psi (138 kPa), the system compensates
automatically to deliver the needed 40 psi (276 kPa).
If,
however, during the same maneuver, the driver steps on the
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