Have you ever driven on sub-optimal road surface conditions? If so, the ESP has probably come to the rescue quite a few times. Thus, it is understandable if you want to reset the ESP light in the Mercedes you own. The electronic stability control of the Mercedes keeps you safe and prevents damage to your car on unsafe road surfaces.
The ESP may be known by other names or aliases like Dynamic or Vehicle Stability Control (DSC or VSC), Vehicle Stability Enhancement (VSE) and Electronic Stability Control (ESC). In all these cases, it provides useful features like hill hold control and hydraulic brake assist. Load adaptive control, roll-over and trailer-sway mitigation, and tyre pressure monitoring are also some functions of the ESP.
What is ESP? How Does It Work?
ESP is short for the Electronic Stability Program. Its primary purpose is to retain control of the vehicle during extreme steering. It will activate if the tires start to lose traction on the road surface. The ESP helps control tire movement during sharp cornering, over or understeering, or slipping. It keeps the vehicle from skidding on the road surface.
Overall, the ESP utilises the ABS sensors on the wheels to monitor their rotational velocities. When any single wheel rotates significantly faster than the other three, it signals some irregularity of the road conditions. The wheel may be slipping. So the ESP applies the brake on that wheel, slowing it down to a speed similar to the others.
Thus, your car stays stable even on slippery roads. To achieve its objective, the ESP works with input from the wheel speed sensors. A steering angle sensor, a yaw rate and a lateral acceleration sensor help. It also communicates with the engine control unit.
What Does The ESP Light Indicate?
The ESP light mostly turns on in two different ways. One is an intermittent flashing of the light, while the other is a constantly ON ESP light. We will tell you what either of these means.
1. A Flashing ESP Light
Flashing of the ESP light indicates that the Electronic Stability Program is operational and keeping your car steady. You may notice this phenomenon is while driving on snow or icy roads. Road conditions like in Mongomery or Sharonville would also engage the ESP. While stability assist is a lifesaver, it has its limits. So, when the light starts flashing, road conditions necessitate utmost caution.
2. If The ESP Light Is ON All The Time
It indicates that the stability control system of the car is not functioning. The ESP is controlled via a button on the dashboard. If you have pressed the button by accident, you may have turned the system off. You can reset the ESP light on your Mercedes by merely pressing the switch again.
On the other hand, some defects in the system could stop the stability control from functioning. In this case, too, the ESP light turns on. If the light does not go away on pressing the ESP button, it is worrisome, indeed. Repair of the Mercedes ESP module may be necessary. Sometimes, the error may affect the ABS at the same time.
Why Did The Mercedes ESP Light Turn On?
What is ESP malfunction in Mercedes? We will discuss the possible causes behind the ESP light’s appearance. The following are the parts that most often malfunction, leading to the ESP light coming on.
- Brake Light Switch: A defective brake light switch could stall the ESP as it won’t know whether the brakes are well applied.
- ABS Wheel Sensor: If the wheel sensor is faulty, then the ESP cannot function since the concept works on anomalous wheel speed.
- Low Battery Voltage: A low battery voltage will hinder the function of any electronic system of your car, including the ESP.
- Fault in the ABS Module: Until you repair the defect, it won’t work.
- Steering Angle Sensor: The steering angle values allow the ESP to respond in cases of over or understeering.
- Other sensors: All sensors ultimately fail due to regular wear and tear.
Ways To Reset The ESP Light In Your Mercedes
How do I turn off the ESP light? There are a few methods you can try. We will start with the obvious and move on to more complex approaches. If you are confident that nothing is faulty with the ESP components, you can directly jump to Step 8.
1. ESP Control Switch
Let us try the obvious option first. Press the ESP switch on the dash. Many-a-times, car owners forget that they had disabled the ESP of their own volition. You might also have hit the button by accident. If that does not fix your trouble, move on to the next steps.
2. Force Reset Via ESP Button
Once you have located the ESP button, press and hold it for five seconds, performing a hard reset of the electronic circuits of the ESP. As you might expect, a hard reset will also turn off the indicator light. A hard reset can help with the issue in the control system of the ESP. Hardware problems, on the other hand, will not go away that easily.
3. Examine The ESP Error Code
The location of the diagnostics port is usually under the dash on the driver’s side. Once you plug the fault diagnostic reader in, you can scan, diagnose and erase fault codes from the car’s computer. The video demonstrates using an iCarsoft i980 reader. However, the iCarsoft MB II or the Launch Creeder VII or VIII are also effective. These devices provide satisfactory explanations of the error codes for your benefit.
Upon checking the error codes, you will know which system is causing the trouble.
4. Reset Steering Angle Sensor
Usually, catastrophic failures do not occur in the steering angle sensor. If this sensor has stopped working, you merely need to reset it, and you will not require any tools. Repeat the turns twice if necessary.
5. Check Battery Voltage
A low battery voltage leads to multiple difficulties in the electronic systems of your car. Check the voltage using a multimeter. The correct voltage is around 14V with the engine running and a little above 12V with the engine off.
6. Replace The Wheel Speed Sensor
If the wheel sensor has failed, you will have found out while reading the error codes. The diagnostics device will also have informed you which wheel speed sensor to remove. Proceed with the steps in the video to replace the sensor. You will need a 10mm and an 8mm socket wrench to remove the wheel arch cover. You may prefer to use a short wrench because of the cramped access space.
7. A Faulty Brake Light Switch
A broken brake light switch also triggers the ESP light. Replacing the switch is a straightforward task. We have a superb article on diagnosing and fixing brake light errors. Check it out if you wish.
8. Clear or Reset ESP Error Codes
Once the faulty part has a replacement or a repair, the ESP light does not turn off on its own. You will have to clear the fault memory. You can use the same diagnostic device you used previously to read the codes. It is the final step to reset the ESP light in your Mercedes.
Can I Still Drive With ESP Light On?
It is possible to drive without the ESP. Many car owners make do without it in the basic car models. If all you will face is city traffic, there is no need for the ESP’s capabilities. However, with the multiple safety features that an electronic stability control brings to bear, it is unwise to continue driving without it.
Even if you expect to drive only in safe road conditions, having a working ESP is better than the alternative. Moreover, you never know when you might need the assist. A failure of the program during snow or ice will be fatal. So, drive carefully and avoid icy roads until you resolve the issue.
A rare possibility is that your car goes into limp mode. It is a safety feature that prevents you from driving in case of a fatal defect in the car’s systems. Depending on what exactly is causing the ESP light, you may face this scenario as well. In limp mode, the transmission does not change gears. You also cannot accelerate above 20 mph.
That is how you reset the ESP light in Mercedes cars. The ESP, while not a critical system, is indeed a prominent safety apparatus in modern vehicles. Studies show that the stability control system reduces fatal accidents by as much as 32%. Hence, do not ignore the ESP light. Any tools you might need are available in any automobile spare parts shop. You can procure diagnostic readers online as well.
All these steps are simple enough to do at home. So, what are you waiting for? Get started.