Electronic Stability Control (ESC)
Warning: ESC is intended only as an aid for a conscientious and alert driver. Carefully read the information in this manual to understand this system and its limitations. ESC is not a substitute for safe driving procedures. Failure to drive safely, and use the system properly, could result in personal injury and/or death and property damage.
Caution: Changing or modifying the location of the ESC sensor or reconfiguring the vehicle, such as by changing the wheelbase or adding axles, can change the performance of the enhanced stability control system and may result in product or property damage and personal injury.
Electronic stability control (ESC) works by constantly comparing the driver’s intention with the vehicle's actual behavior. The system does this by monitoring wheel speed, steering angle, yaw rate, lateral acceleration, throttle position, and brake application. A central microcomputer analyzes the collected data and triggers a response to keep the vehicle on course when an unstable condition is detected.
When the system detects that the vehicle is at risk of over-steering or under-steering, it applies individual tractor wheel end brakes and trailer brakes and/or cuts power to reduce the likelihood of a drift-out or jackknife.
If the acceleration sensor detects the vehicle is at risk of rolling over, the roll stability control system within the ESC automatically reduces power and applies the brakes.
Yaw control is not active below approximately 6 mph (10 km/h). Roll stability control is not active below approximately 12 mph (20 km/h). At higher speeds, ESC operates automatically; the driver does not monitor or activate the system.
The driver has full control over the vehicle until the system detects a potential risk and intervenes accordingly.
The ESC telltale, as shown in Fig. appears on the driver display when ESC intervenes and when ESC is unavailable due to a fault. The ESC telltale flashes when an ESC event is actively occurring and is solidly illuminated when ESC is unavailable due to a fault.
Fig. 1, Electronic Stability Control (ESC) Telltale
It is normal for the ESC telltale to illuminate shortly after a curve, lane change, or other driving maneuver that results in ESC detecting a rollover-risk.