© 2018 Pierce Manufacturing Inc. All Rights Reserved.
Driving the Vehicle / 5-57
OPERATION
The type and magnitude of an RSC intervention depends on the amount that the actual vehicle lateral acceleration
exceeds the control limit. Intervention starts with an engine torque reduction command (you may sense a decrease
in engine power), followed by application of the engine brake
(if the vehicle has an engine brake, you will feel the
additional deceleration)
, and if necessary, application of the drive axle brakes (you will feel braking take place).
For additional RSC information, refer to the Pierce Service Manual, group 0251-V-015, Meritor Wabco Anti-Lock
Braking System (ABS) and group 0995-V-003, Meritor Roll Stability Control (RSC) Driver Tips.
5-30.3 Electronic Stability Control (ESC)
Electronic Stability Control (ESC) is designed to stabilize the vehicle during cornering maneuvers. ESC checks
where you are steering and where the vehicle is actually going. ESC applies the brakes at individual wheels and
intervenes in the engine management system to help point the vehicle in the direction that you are steering.
During normal driving, ESC works in the background and continuously monitors steering and vehicle direction. It
compares the driver's intended direction (determined through the measured steering wheel angle) to the vehicle's
actual direction (determined through measured lateral acceleration, vehicle rotation (yaw), and individual road wheel
speeds).
ESC intervenes only when it detects loss of steering control, i.e. when the vehicle is not going where the driver is
steering. This may happen, for example, when skidding during emergency evasive swerves, understeer or oversteer
during poorly judged turns on slippery roads, or hydroplaning. ESC estimates the direction of the skid, and then
applies the brakes to individual wheels asymmetrically in order to create torque about the vehicle's vertical axis,
opposing the skid and bringing the vehicle back in line with the driver's commanded direction. Additionally, the
system may reduce engine power or operate the transmission to slow the vehicle down.
ESC can work on any surface, from dry pavement to frozen lakes. It reacts to and corrects skidding much faster and
more effectively than the typical human driver, often before the driver is even aware of any imminent loss of control.
It is important to understand that ESC is not a performance enhancement nor a replacement for safe driving
practices, but rather a safety technology to assist the driver in recovering from dangerous situations. ESC does not
increase traction, so it does not enable faster cornering. More generally, ESC works within the inherent limits of the
vehicle's handling and available traction between the tires and road. A reckless maneuver can still exceed these
limits, resulting in loss of control. For example, in a severe hydroplaning scenario, the wheels that ESC would use
to correct a skid may not even initially be in contact with the road, reducing its effectiveness.
5-30.3a ESC Brake Noise
When ESC is operating you may hear air brake pulsations and feel engine power reduction during aggressive
maneuvers. These are normal conditions that indicate the system is working to improve stability control.
Electronic Stability Control (ESC) is an electronic system designed to help the driver maintain vehicle
control under adverse conditions. It is not a substitute for safe driving practices. Electronic stability
control is only a driving aid; all normal precautions for driving in inclement weather and on slippery
road surfaces must be observed. There is NO substitute for the Safe Driver
Never drive too fast for the road conditions or too quickly when cornering. Electronic stability control
(ESC) will not prevent accidents. Excessive speed in turns, abrupt maneuvers, and hydroplaning on
wet surfaces, and driving onto soft shoulders can still result in serious accidents. Only a safe and
attentive driver can prevent accidents by avoiding maneuvers that cause the vehicle to lose traction.
Even with the ESC installed, always follow all the normal precautions for driving - including driving at
safe speeds for the conditions.
Summary of Contents for Enforcer
Page 1: ... 2018 Pierce Manufacturing Inc Part No PM C OM014 SEN 0718 Operator s Manual Saber Enforcer ...
Page 2: ......
Page 18: ...FOREWORD 1 6 To the Owner and Operator 2018 Pierce Manufacturing Inc All Rights Reserved ...
Page 30: ...SAFETY 2 12 Safety and Responsibility 2018 Pierce Manufacturing Inc All Rights Reserved ...
Page 122: ...OPERATION 5 60 Driving the Vehicle 2018 Pierce Manufacturing Inc All Rights Reserved ...
Page 184: ...A 4 2018 Pierce Manufacturing Inc All Rights Reserved ...