If you drive a modern vehicle, it is possible that it has a bunch of electronic nannies watching your back. Many of these systems have dedicated warning lights to let you know when something goes wrong. The Traction Control light is among them. No points for guessing which system’s trouble it indicates.
Unlike most other warning lights, seeing the traction control light coming on can be a good sign. But just like other warning lights, it could be a bad sign as well. But how can you determine what your traction control light indicates? How do you determine if it is a relief or if it smells of trouble? Are you confused? Allow us to explain this story.
What Is Traction Control?
To learn about the traction control light, you must know what the traction control system is. All modern cars come with a plethora of electronic safety systems protecting the occupants from many possible accidents. This includes your anti-lock brakes, Corner Braking Control, Brake Assist, collision avoidance systems, and plenty more. If you like abbreviations like TCS, ESC, HDC, AYC, and so on, this is the part to read up on. Traction Control is a system that is offered with this.
These are generally offered as a suite of electronic systems that share data from a bunch of sensors. They process the data in their own ways and then use that to warn about or avoid impending hazards. Most of these systems have indicators on the dashboard or instrument cluster, to alert the driver of any failures. The traction control light is an indication device for the traction control system, as a part of this elaborate system.
What Function Does The Traction Control Have?
As its name points out like a well-trained pointer mutt, Traction Control watches over the traction at the wheels. On our daily drives, we may encounter slippery surfaces on the road. It may be a small patch of spilled oil from another vehicle, an overspill from a fuel tanker, heavy rain, or a thin layer of snow.
No matter what they are, they reduce the traction between the tires and the road. This reduction in traction is felt by the driver in the form of wheel slip while accelerating, a sudden lockup when braking, or losing grip while cornering.
Traction Control is employed to take care of the acceleration part. If you are driving in the wrong gear while treading over a slippery patch, the throttle can be tricky to handle. Going hard on that throttle while your tires are already struggling for grip is not the wisest move. The tires will spin uncontrollably, and you will lose a lot of power. This is even more apparent when you try to climb a slippery slope. This is where the traction control comes to the rescue, along with the traction control light.
What Does Traction Control Do?
As we have already established, acceleration on a slippery surface is right in the Traction Control’s wheelhouse. This system uses wheel speed sensors to understand and analyze the speed at which each wheel of the car is spinning. This data is fed into the Electronic Control Unit (ECU) for processing.
Under hard acceleration on slippy planes, the wheels in contact with the low-traction area will start spinning uncontrollably. The wheel speed sensor data will tell the Traction Control system about this. It kicks in and prevents the wheelspin by doing either of the following two things or both.
Braking Individual Wheels
This is where the Traction Control System seeks help from the Anti-lock braking system. The wheel that is detected to be slipping is given controlled braking pressure by the ABS. Instead of applying the complete brake pressure at once, the ABS slowly brakes the wheels intermittently. This braking reduces the slip, and the vehicle can move ahead safely.
Controlling The Engine Output
The Traction Control system works with the powertrain control computer to limit the engine power going to the wheel. This is done in several ways. These include electronically limiting throttle input, controlling the flow of fuel, managing the ignition spark, or even shutting down cylinders altogether. Limiting the power going to the slipping wheel will reduce the torque on it, ultimately, killing the uncontrolled slip.
This helps the traction control system control the wheelspin effectively. With the traction control, you can drive on friction-less surfaces safely. So, a traction control light can be a cause of worry.
If you want to experience it in action, try punching the gas of your vehicle on a wet or icy day. You can see the revs climbing but the tires will hesitate to comply. They will simply cut back and forbid you from spinning your wheels. But never try this stunt on a public road. Always find a secluded parking lot or private area to try it out. Trying the traction control on a public road is a reckless antic that can put you and your fellow road users in danger. So, tread wisely.
So, I Should Always Leave The Traction Control On, Right?
Eh, not really. It is true that a traction control system saves you from embarrassing wheelspin on an ice-covered public road. But there are instances where wheelspin can be a visual delight. Wheelspin, screeching tire noises, smoke, loud exhausts, get it? Yes, burn-outs. Basically, anything that has to do with spinning tires. Donuts, drifts, burn-outs, the lot. Almost every act a professional stunt driver does on a closed area (and not on the public road).
The traction control system’s operation can be an intrusion while a professional driver performs these things. These stunts thrive on the very principle that tires spin over anything slippery. So, a system like TCS that prevents it, can be a pain for them to handle with.
Most of the drivers who are trained to perform these stunts turn the traction control off for this very reason. For them, a forever-illuminated Traction Control light is not a happy sight. This may be apt on a closed circuit or drag strip. But on a public road, on your way to the school with your children at the back, TCS is better left turned on. Schools don’t seem to like tire smoke in their compound.
How Do ESP, ABS, And TCS Differ From One Another?
Most drivers will be familiar with anti-lock brakes (ABS)., it prevents locking up of wheels under hard braking when they find grip hard to come by.
Electronic Stability Program (ESP) also known as VSC, ESC, and gazillion other names is a similar feature. It helps prevent drivers from losing control of their vehicles as they steer at high speeds on a slippery surface. Here, you can read on how to troubleshoot an ESP system if that in your vehicle is acting up.
In a nutshell, on any slippy plane, TCS lets you drive forward safely, ABS lets you brake safely, and ESP lets you turn safely. If you need a visual aid to understand the concepts better, the following video will be a good source.
Traction Control Light
The light is dedicated to alert the driver of the functioning or malfunctioning of the TCS system is the traction control light. In the following sections, let us learn more about what it does, what it looks like, and what causes it to come on.
What Does A Traction Control Light Look Like?
In different vehicles, the traction control light takes different forms. You may think that it can be confusing but fret not, there are standard lights, one of which appears on almost all vehicles. The first one includes the letters “TC” encircled with a dashed outline.
The second icon shows the outline of a car with two skid marks under it. The third light includes the words TC enclosed in a special shape with slots on the base. All these lights will mostly be illuminated in yellow. Irrespective of their design, all traction control light types indicate the same thing.
When Does It Come On?
Unlike other warning lights, the traction control light mostly comes on to indicate the proper functioning of the system. In other words, the traction control light comes on when the traction control system is working. For instance, when you are driving on a road covered with a thin sheet of snow, the traction control light will either stay on for a few seconds or blink. This is because of the fact that the traction control system is working tirelessly to keep your wheels gripping onto the road.
The illumination of the traction control light is thus a happy sight as it tells you that the system is flawless. Unlike ABS light, it does not always mean trouble. But when does it turn into an issue? If it denotes proper functioning of the system, when is it cause of worry?
You can judge what the traction control light means, by considering the surface you are driving on. If it is a slippery surface, it is perfectly fine for the traction control light to come on, blink for a while, and then disappear. But if you are driving on perfectly fine tarmac, a traction control light can mean trouble.
What Does It Mean?
Your traction control light may come on and blink during a normal drive. This can mean that there is a problem, but it is not “hard-coded” yet. This means that the problem is not permanent yet, but it is creeping in. The traction control system is slowly losing its integrity and can fail sometime in the near future.
If the light stays on without blinking, your traction control system is already deactivated. In some vehicles, the warning light will be accompanied by a message in the instrument cluster. If these happen, it will not be a bad idea to be extra careful while driving over snow, or water on the road.
If it is disabled, it is crucial that you take the vehicle to the nearest garage and check the system. It may be safe to drive it in normal weather. But if you are about to drive in rain, snow, or gravel, it is good to have traction control.
What Causes The Traction Control Light To Come On?
There is only one way to pinpoint the problem that causes the traction control light to come on. It is to take the vehicle to a garage and diagnose it. Qualified garages can easily troubleshoot by doing a full computer systems scan. This can bring up error codes that pertain to either the traction control system directly or other parts that can cause the traction control light to illuminate.
A malfunction in some other parts can also bring about an error that can light up the traction control light. It does not necessarily have to be a problem with the traction control system or its peripheral parts. Let us understand some of the major issues that can light up the traction control light like it is Christmas.
Wheel Speed Sensor Covered In Dirt Or Debris
The wheel speed sensor is the primary input device for the traction control system. The reading from this sensor is paramount for the TCS to take decisions. Normally, the wheel speed sensors are placed closer to the wheel, an area exposed to natural elements. Even though it will be protected, dirt, grime, and other debris can throw up onto the sensor and clog it.
A sensor covered with grime may not be able to judge the speed of the wheel properly. When this incorrect info is fed into the TCS brain, it can end up making wrong calculations. But the vehicle’s computer is brilliant enough to find it and alerts the driver through the traction control light.
Faulty Wheel Speed Sensor
Now we know that anything related to the wheel speed sensor can directly affect the traction control system. A similar result can be expected if it conks out after thousands of miles of running. In some instances, it does not even have to be an old sensor. Even new ones can go wrong, triggering unintended braking. GM learned it the hard way and ended up recalling 675,000 of their SUVs and trucks back in 2019.
Ensuring the optimum well-being of the wheel speed sensor is of great importance. It might be hard to know the condition of the sensor until it fails. But getting the vehicle diagnosed the moment the traction control light comes on is a good practice.
If you choose to replace the wheel speed sensor yourself, it will cost you just over $100. An OBD2 scanner can help you pinpoint the faulty sensor. Taking it to a garage will set you back close to $150, if not more. If your knowledge about working on cars is not that great, the extra bucks spent in a garage are well worth it.
Here is a short video for anyone who is planning on swapping it themselves
Problems With The ABS Module
As we know, the traction control system and ABS work hand in hand. Hence, anything that goes wrong with the ABS systems can end up spoiling the TCS operation as well. The wheel speed sensor was one of these. On the other end of the circuit, a problem with the ABS control module can throw a traction control light. In this case, you may also see the ABS light glowing along with it.
This is not an inexpensive fix. So before confirming that it is the ABS module that has gone the way of the dodo, get it scanned. A simple scan using an OBD2 scanner can point at the real problem.
If it is just a wheel sensor, you can fix it for just over $100. But if it is the ABS control module, your wallet will become lighter by around $1000. But at least, we’ll finally get to turn the traction control light and the ABS light off.
The Traction Control System Needs Reprogramming
If an OBD2 scan does not return any error codes pointing at the wheel speed sensor or ABS module, the TCS may need a simple reprogramming. This does not have a DIY fix. However, a certified mechanic can do it for you. It will not take more than an hour or make you spend more than $150 – $200.
Problems With The Traction Control Switch
This is not an issue that may kick up the traction control light. Most cars come with a traction control switch that helps the driver turn the TCS on or off. Sometimes, the traction control may continue functioning even when the switch is turned off. This will illuminate the traction control light of course, but only indicate that the TCS is working.
The driver may also be unable to turn it off when needed. The logical explanation for this will be a fault in the traction control switch. If this is so, a malfunctioning switch can leave the TCS on even after manually turning it off. But, in some rare cases, this can also mean that there is an issue with the TCS system itself.
Replacing the switch will cost you from $120 to $150 depending on the model. It needs a visit to the garage, but at least then you breathe a sigh of relief. It is comforting to know that the traction control system is functioning properly behind that broken switch.
What Happens If You Drive With The Traction Control Light On?
The traction control light does not indicate an upcoming catastrophic mechanical failure or electrical meltdown. It is almost seemingly safe to drive your car during normal weather conditions with the traction control light beaming like a floodlight. You will find no difference in the way your car handles or drives. This can lead many drivers to be complacent when it comes to fixing the traction control system.
But given that, when the condition worsens, if it rains, snows or you drive over a hypothetic mile-long patch of spilled engine oil, things can get nasty. Under heavy acceleration, the tires will squirm without grip on these surfaces. This can get even uglier if a wheel speed sensor error has caused the ABS to stop working too.
With the TC and/or ABS disabled, it is a safety hazard to drive under these conditions. The vehicle can lose control while accelerating or braking. So, if you have a traction control light glowing at you, drive to a nearby garage if you feel that the weather is safe to do so. Else, drive with extreme caution and get the problem sorted as soon as possible.
Which Cars Are The Most Prone To Traction Control Problems?
Traction control appeared on production cars in the 1970s for the first time. These were rear-wheel-drive performance cars. But it never went mainstream until 1987, when manufacturers like Toyota and Mercedes Benz started offering it. It has been made mandatory from 2012 for all cars and trucks sold in the United States to offer TCS.
If there is a TCS system in your vehicle, there is the possibility of a traction control light popping up. So, if your vehicle offers traction control, it can fail at some point and give you a traction control light. Anything built after 2012 is bound to have TCS in them, so owners of those vehicles need to be aware of what traction control light indicates.
Even some of the most reliable manufacturers had to issue recalls due to issues with the traction control systems. The traction control light is neither an issue that affects the reliability of your car nor does it render your vehicle unusable. But as a safety system, if it is present in your vehicle, it is good to keep it functioning.
Traction Control Light: A Big Issue Or Not?
As we have seen, several issues can cause the traction control light to come on. Illuminated traction control lights can be scary to some drivers. But now, it must be clear to you how easy it is to spot and solve this issue. But even though the traction control light indicates no grave mechanical errors, it is not to be taken lightly.
Will you continue driving your car if you know that the airbags do not function? Will you be at peace if the ABS has died on you? Similarly, a traction control light is to be taken seriously. This is paramount for the smooth operation of the traction control system. Ultimately, the TCS, ABS, and ESP together keep your vehicle running safely and smoothly.
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