One of the displays that a driver hopefully rarely sees is the ESP light. Learn more about the function of the ESP system, possible sources of error, and causes of ESP light up in the car. At the same time, you will find information on what is ESP in a car & what to do if ESP lights up on the car.
With the increase in electronic systems and car safety innovations, the driver’s workplace looks more like an airplane cockpit. Countless displays, lights, sensors, and warning signals monitor every meter and report changes and defects immediately.
What is ESP in a car?
The abbreviation ESP stands for Electronic Stability Program. Behind this bulky term is the combination of several systems of vehicle electronics. ESP only intervenes in critical situations. Typical applications include wet roads or excessive centrifugal forces when cornering.
If individual wheels threaten to lose their grip on the road surface, this is detected by the corresponding sensors.
How does ESP system work in a car?
The electronic stability program uses sensors to detect when the car is in danger of skidding and swerving. More precisely, the system determines the driver’s steering movement and also measures the car’s lateral acceleration. If the data obtained from the sensors show that the steering angle and the direction of travel do not match, the anti-skid system intervenes.
It reduces engine output and selectively brakes individual wheels to stabilize the car again. ESP counteracts rear-end swerve or oversteer of the car in a curve, by braking the outer front wheel. To prevent understeer, it acts on the inside rear wheel. ESP evaluates the ABS speed sensors at the wheels, the steering angle, and information from a yaw rate sensor.
In this way, it constantly compares whether the vehicle is moving as the driver specifies through the steering. In the event of an oversteer or understeer, the system intervenes by selectively applying the brakes. This keeps the vehicle in the lane selected by the driver.
When the ESP lights up in a car?
The ESP indicator is usually a yellow or orange light showing a car with two ruts. In some manufacturers, the indicator is framed by a triangle. You can find the ESP indicator in the instrument cluster of the cockpit. Most often, the ESP light can be seen briefly after turning on the ignition until the system is ready for use.
ESP light lights up
During everyday driving, the ESP light does not light up. If the ESP indicator lights up, it means that the vehicle electronics have detected a need for action and that the ESP is currently intervening in a regulating manner by braking one or more wheels. For example, this may be the case if the vehicle is cornering too fast, in the event of aquaplaning, or in sudden braking and evasive situations.
ESP lights up permanently
If the blinking rhythm of the ESP indicator changes or the light lights up continuously during everyday driving, this is a sign of a malfunction. It means that the car’s onboard electronics have switched off the stability support.
The reasons are often a defect in the ESP system, which you must diagnose precisely. There is no immediate danger for the driver or the car after the ESP has been switched off because the drive, brakes, and steering continue to work as usual.
What can you do if the ESP lights up permanently?
ESP is an important safety system, and its intervention can be helpful even at the next traffic light. If the ESP light is permanently on, you should drive more carefully and consciously. Steer carefully and avoid extreme braking maneuvers.
In any case, don’t wait long to have your ESP repaired. Insurance companies may check if the ESP was working in the event of an accident. Thus, you could lose insurance coverage in the event of an accident. During a general inspection, the experts will check the ESP support during the general inspection. Your car will not pass the main inspection without functioning ESP.
Possible causes of the ESP lights up in a car
Some car manufacturers make it possible to switch off the ABS and ESP at the push of a button. This is to make braking on gravel surfaces easier. Unless the car’s ESP stability program has been deliberately deactivated manually by the driver, a repair is inevitable if the ESP light is permanently lit.
To do this, a workshop must first perform a comprehensive and professional diagnosis to find the fault. After all, numerous sensors are involved in ESP. It is conceivable that there is a problem with the steering angle sensor, the wheel speed sensor, the rotation rate sensor, or the lateral acceleration sensor. The car’s control units for ASB, ASR, and ESP are also possible sources of error. But you can also hide a fault in the cables or the bus system.
Troubleshooting for ESP that lights up
You can only obtain more precise information from a workshop because this requires a great deal of experience and special equipment. Drivers cannot help themselves if the ESP is defective. The workshop’s most important tools are the diagnostic system and oscilloscope.
In the first step, the specialist connects the diagnostic device and reads out the fault memory. This usually gives an indication of where to look for the fault. It is somewhat more complicated if the defect only occurs occasionally.
But even for this, the specialist knows a solution. In these cases, a test drive is recommended to reconstruct the error. Often a too low onboard voltage, a defective brake light switch, or a problem with the ABS are the cause.
Defective sensors can also cause the problem because the ESP electronics receive faulty impulses or none. The workshop can check the sensors with an oscilloscope.
Repairing an ESP in the workshop
Replacing one of the sensors that cause the ESP light to light up is relatively easy. For example, the ABS sensor sits directly on the wheel hub. The price of a new speed sensor varies greatly and depends on the vehicle type and make. Some additional work is also required for the repair.
For example, the respective wheel must be removed and installed, new cables may have to be laid, and the control unit must be relearned. After a test drive and another computer diagnosis, the repair is complete, and the light should only report when the system is actively working.
What is the difference between ESP and ESC?
The terms ESP and ESC both describe the driving assistant for vehicle dynamics control. The different terms used to be branded by different manufacturers. The term most commonly used today is ESC. Those who want to be neutral use driving dynamics control.
ESP – “must have” for novice drivers
It is obvious that ESP is not a panacea for accidents caused by unreasonable driving. Nevertheless, the assistance system proves to be an enormous plus in terms of safety. Because novice drivers and occasional drivers quickly oversteer or understeer the car in curves or on slippery roads due to a lack of driving experience, ESP should not be dispensed with in a beginner’s car. When buying a used car, it is generally advisable not to skimp on safety.