The Electronic Stability Control (ESC) system is a piece of innovative technology that gives vehicles extra stability and traction, especially when the vehicle is driven at its limit. Depending on the vehicle, it may also be referred to as:
- Electronic Stability Program (ESP)
- Dynamic Stability Control (DSC)
- Vehicle Stability Control (VSC)
- Vehicle Dynamics Control (VDC)
This technology works in conjunction with the vehicle’s engine control unit. Whenever the car begins to lose traction on the road, the sensors in the wheels will provide this information to the computer.
This will cause the computer to automatically activate the brake on one or more wheels to stop the vehicle from swerving out of the lane or road. If you oversteer or understeer, you can expect this to happen then too.
What Electronic Stability Control Monitors
To understand the functions more clearly, here are the top functions of the electronic stability control system.
1) Senses Wheel Speed
Like previously mentioned, the system can determine the speed of all your wheels. Once this information is relayed to the computer, it will be able to calculate the amount of braking power that it will take to slow down the wheels.
2) Position of the Steering Wheel
There is a sensor in your vehicle that tracks your steering so that it knows which direction you want to go. If the vehicle starts to move in a different direction than where you’re trying to steer, the electronic stability control system will apply one or more brakes to correct the vehicle’s until it matches the steering angle and intent of the driver.
3) Avoid Fishtailing
The rear wheels of some vehicles might lose traction before their front wheels do. This is known as fishtailing and it is one of the main reasons that drivers oversteer. You will likely experience this problem on the road under bad weather conditions.
Fortunately, the electronic stability control system can detect when fishtailing might happen. Then it will apply the brakes to avoid it.
4) Turn Stability
Vehicles have a lateral acceleration sensor that can track how fast you’re turning your vehicle. If there is too much steering or not enough steering, the sensor will be able to tell. From there, the electronic stability control system will fix the problem.
5) Rollover Resistance
Some vehicles are top heavy, like trucks and SUVs. Many vehicles with a higher center of gravity rely on stability control to keep the vehicle from tipping over during sudden serpentine movements. One example of such movements is the moose test.
Symptoms of an Electronic Stability Control Malfunction
If you have a malfunctioning electronic stability control system, you will likely have a harder time controlling the vehicle if there is a sudden loss of traction, like you would experience on ice or snow.
Below are the top 4 symptoms of electronic stability control technology problems. If you notice any of these symptoms, then get it fixed immediately.
1) Warning Light
If there is a problem with your electronic stability control system, a warning light will illuminate on your dashboard to let you know it. You may also receive some troubleshooting codes if your car gives them to you. Either way, this warning light is an indication that you have a problem with this system.
2) Bad Traction
The electronic stability control system is supposed to keep the vehicle stable on the road. Obviously, if there is a problem with this system then it will affect the stability of your vehicle. This means the traction will be bad, causing you to swerve out of your lane on the road.
3) Brake Issues
The anti-lock braking system is connected to the electronic stability control system. This means that when the latter goes bad, you might notice problems with your braking as well. Your brakes will still work, but you may not have ABS if you need to stop quickly.
4) Loss of Control
If your stability control system stops working and you’re driving in bad weather, you might be on your own without the computer to assist you. Keep a healthy following distance and try not to make sudden movements that could upset the balance of the vehicle.
Do All Cars Have Electronic Stability Control?
Nearly all modern cars have electronic stability control. If you own a vehicle from the 1990s, it is possible that vehicle does not have electronic stability control. A vehicle with electronic stability control will also have traction control.
ESC Light On vs Flashing
If the ESC light stays on, you have either defeated stability control, or there is a problem with the stability control system that will prevent it from working if you lose traction.
If the ESC light flashes intermittently, the stability control system is actively stepping in to correct the vehicle’s course. You are much more likely to see the stability control light flash when you accelerate aggressively or drive in slippery conditions. This is typically seen during normal operation.
Read Also: 5 Reasons the Check VSA Light Is On
What Can Cause the Stability Control Light to Come On?
1) Bad ABS Sensor
Stability control needs the ABS sensors (also called wheel speed sensors) to precisely detect how fast each wheel is spinning. If one wheel speed sensor gives the ECU erroneous data or stops working, the ESC light will turn on.
This light is often accompanied with a second warning like “Service AdvanceTrac” for Ford vehicles. You will also likely notice the ABS light turn on.
2) Bad Steering Angle (Yaw) Sensor
Inside the steering wheel there is a steering angle sensor that detects how far you’ve turned the wheel in either direction. This helps the ECU know where you’re trying to go, and allows the ECU to detect understeer and oversteer conditions.
If your steering angle sensor goes bad, you will see the stability control light turn on. Some vehicles may throw a code for this or illuminate an additional warning light as well.
3) You Turned Off ESC
It is possible to fully defeat electronic stability control in most vehicles. When you turn off traction or stability control, the lights will remain illuminated to remind you that those systems have been turned off.
What Does “Service Electronic Stability Control” Mean?
When your instrument cluster asks you to service the electronic stability control system, it has detected a fault that may prevent the stability control system from working correctly. This could be due to a bad sensor, a bad ground, or a problem with one of the vehicle’s electronic modules.
Is There Any Reason to Turn Off Electronic Stability Control?
There are valid reasons for intentionally defeating stability control. Here are some example scenarios where stability control might slow you down.
1) Driving in Deep Mud, Sand, or Snow
Sometimes a vehicle’s traction and stability control systems will cut power as your wheels start to slip. If you’re stuck in deep snow, sand, or mud, this torque reduction could make it difficult or impossible to free a stuck vehicle.
Defeating the traction control allows the tires to spin freely which can help get you out of a tough situation where you are traction limited. If you need to defeat stability control to free the vehicle, don’t forget to turn the system back on after you’re done.
2) Performance Driving
In many performance driving events such as autocross and rally, the stability control system can hurt your lap times. Stability control systems want your car to drive straight with no wheel slip, but some courses are faster to run if you know how to rotate the car around the corners.
The subtle slide that results from perfect rotation may cause the stability control system to fight against your inputs. The less grip you have, the more likely you are to want to defeat stability control to set the fastest lap times.
Note: if you are unfamiliar with a vehicle, you should leave stability control on until you are comfortable with the car. This is especially true for high-powered rear wheel drive vehicles, like Mustangs and Corvettes.