This light is switched on automatically as soon as the vehicle detects that you are driving in slippery weather conditions.
The VDC plays the role of reducing engine power and at the same time braking the wheels that have lost control. In most cars, the slip light on the dashboard illuminates to indicate that you are approaching a slippery road. If the VDC light malfunctions, the VSC OFF light will illuminate.
Common VDC Light Causes
The traction control will not function properly forever. When this happens, the light will be on all the time. Here are the main reasons for a faulty VDC light:
1. Faulty wheel sensors
Sensors are attached to each of the car wheels. The function of the sensors is to detect any shift in the wheel angles and send this information to the on-board computer. When you accelerate, the sensors detect the speed of each wheel. If one of the wheels slips and turns faster than the others, the ABS on these wheels is activated.
It also reduces the power of the car, giving you better control over the car. If the wheel sensors are faulty, no over- or under-steering is detected, which means that the lights will still go on or off. Wheel sensors often accumulate dirt, which makes them ineffective. You can remedy this by taking your car to a mechanic who will clean the sensors and at the same time ensure that the wiring is in good condition.
2. Poor roads
While the main function of the VDC is to help you keep the car stable when driving on slippery roads, the light will malfunction in extreme road conditions. In some cases, there are those who drive their car on extremely bumpy or snow-covered roads. The traction light will remain on and be of little help. However, as soon as you start driving on open roads, the traction control will return to normal.
3. Faulty steering angle sensors
Each of the wheels with traction control has steering angle sensors. These sensors detect the angle of the wheel when driving on bad roads. Since the sensors are located on the steering column, malfunctions can occur. As a result, the traction control light will come on even if you are driving on smooth roads. A mechanic can take a close look at the sensors and clean them. He can also check the wiring.
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4. Onboard computer programming issues
The wheel sensors are in constant communication with the on-board computer. The computer detects when the wheels slip and sends signals to the ABS or the engine to cut the power supply. As with other computers, the car’s ECU can develop errors. These errors cause the VDC light to illuminate when it is not required. You can solve this by reprogramming the computer. However, reprogramming is a serious issue and you must contact the car manufacturer or a certified mechanic.
5. Bad steering rack
A good steering wheel helps you to control the car when driving on slippery roads. The rack is located on the steering wheel and uses hydraulic fluid to turn the steering wheel. If the rack does not work as expected, you will have problems steering the car even when the VDC light is on.
VDC Light Function
Vehicle Dynamic Control (VDC) works in conjunction with ABS to provide traction to the vehicle. Most of the time, the driver experiences some form of vibration on the brake pedal when VDC is engaged. This should not be a cause for concern as it indicates that the system is working properly.
The confusion about VDC arises when drivers become too confident about their driving ability and rely solely on traction control. Note that over-steering at high speeds can lead to serious accidents. Using the VDC does not eliminate the need to be careful when driving on the road. When making modifications to your car, do not replace struts, shock absorbers, stabilizer bars or springs as they will interfere with the car’s VDC system. The VDC system will also be affected if you change to non-standard brake discs and pads.
In some cases, the VDC is switched on and off when you drive on bumpy roads. This should not be a cause for concern. Wheel sensors attached to the wheels can react to bumpy roads.
How does the VDC work?
Modern cars are equipped with traction control systems that prevent under- and oversteer on slippery roads. The moment the VDC is activated, the brakes on one or more wheels are applied and the vehicle starts to skid. This is followed by a reduction in engine power. One or two of the spark plugs in the combustion chambers are suppressed. In addition, the fuel in one or more cylinders may be reduced. As a result, the engine power is reduced while the driver gets power over the steering wheel. In turbocharged vehicles, traction control will reduce boost pressure by operating the boost pressure control solenoid.
The VDC is designed to give the driver more control over his car during skidding. This is achieved by making the car more stable when driving on snowy roads. The car’s wheels have sensors that detect when one of the wheels is spinning faster than the others. This is done in cooperation with the ABS and the on-board computer.
The VDC is an essential part of the vehicle’s traction control system. The system uses information transmitted by wheel sensors at each wheel. Every time you drive on slippery roads and start to lose traction, the VDC is activated. The VDC works in conjunction with the ABS to lock wheels that are spinning faster than the others.
The wheel sensors also transmit information to the on-board computer, which then reduces engine power. Once VDC is activated, you will find that you have more control over the vehicle than before. The VDC light can become faulty at times and will continue to light up even when driving on slippery roads. You should check the wheel sensors and make sure they are not dirty.
Hi, I’m Magnus, the owner and the writer of Mechanic Base. I have been working with cars for 10 years, specialized in diagnostics and troubleshooting. I created this blog because I was tired of finding false information on the web while looking for repair information. I hope you enjoy my content!