In this guide, we will discuss what does TC mean on a car?
TC means “traction control” on a car. Traction control in the car or truck is a stability system that assists the acceleration process in a car and prevents overspinning on wet terrains. It is used to prevent the wheels from slipping or skidding on slippery surfaces such as ice or snow. It does so by making sure that the wheels stay firmly attached to the ground. This helps in preventing the car from spinning out. The traction control system consists of a series of sensors and controls that work together to help the driver maintain traction. If the ECU detects any fault in the traction control system, your car dashboard will display a “Service Traction Control” message.
We’ve all heard of traction control systems, and we’ve all seen them on our cars. However, what does traction control mean? In this post, we’ll explain how traction control works, and why drivers need to know how to drive with it.
Table of Contents
What Is The Meaning of a Traction of Car Wheels?
Traction of car wheels or tires is simply friction between the moving wheels and the road surface that results from the rotation of a wheel. If there is no friction between the wheel and the road surface, the wheel will not roll over the road, and hence, there will be no traction. The traction of a tire depends on the width of the tire, pressure in a tire, and the force exerted on the tire of a vehicle.
Being a mechanical engineer, I have studied how car wheel actually rolls over the road. Basically, when a wheel gets rotational power from the engine, it tries to push the road surface in the opposite direction to move forward. As a result, the road surface exerts a force in the opposite direction to the force exerted by the wheel on the road surface. This force exerted by the surface on the wheel is called a traction force, and this force is responsible for the rolling of a tire. I have tried to demonstrate it in the image below:
In simple words, traction is a measure of the resistance offered by the surface on which the vehicle is moving to the tire. When a tire has a larger width, the point of contact of a tire with the surface will be larger. So, there will be more traction.
When a greater force is exerted on a car tire, there will be a more gripping force with which the tire of a vehicle is spinning on the surface. As a result, the traction force of a wheel or a tire will increase. Due to this reason, when a car is accelerated, the rear suspension of a vehicle compresses slightly and increases the available grip at the rear tires. If that friction between the vehicle tire and the road surface becomes zero, the tire will stop rolling.
Now, when a vehicle moves over a wet surface, all tires of a vehicle rotate with different velocities as they experience different friction forces.
The tire on the wet or slippery surface will experience negligible friction, while the tires on the dry surface of the road will experience some amount of friction force. If there are different levels of traction on right and left wheels of a car, torque will exert which will cause the car to spin out. I have explained this concept in the image below:
How Traction Control System Works In a Car?
The traction control system in a car works by sending wheel speed signals from the wheel speed sensor to the engine control unit (ECU) while accelerating on slippery or wet surfaces.
ECU unit analyzes the wheel speed and slows down the vehicle to prevent over-spinning. The traction control system is designed to help prevent the wheels from locking while driving on slippery roads or icy conditions.
Wheel speed sensors are used to determine the vehicle’s speed by measuring the rotational speed of the tires. The ECU sends signals to the brakes to reduce the wheel speed.
The traction control system of a vehicle works with the following components:
- Wheel speed sensors
- Electric control unit
- Hydraulic control unit
The wheel speed sensors are attached to all four wheels of a car or a truck. Wheel speed sensors are electronic devices that detect the rotational speed of wheels.
If one of the wheels is spinning at a much faster speed than the other three, the sensor will detect this. The sensors are connected to the vehicle’s engine computer which in turn sends a signal to the brake system (ABS – antilock braking system) to apply the brakes to the fast-spinning wheel to slow down the car.
To slow down the fast-spinning wheel of a car due to slipping surface while accelerating, the engine control unit (ECU) sends signals to the hydraulic control unit of a car, which is present in the ABS.
The hydraulic control unit consists of an electric power motor that drives the hydraulic pump in the braking system and a solenoid valve that controls the oil flow to the brake calipers attached to the car wheels.
In some cases, when both driven wheels of a car start losing traction and spinning faster while accelerating on slippery surfaces, the engine control unit of a traction control system will reduce the wheels’ speed by reducing the power output of the engine. ECU of the engine does the job of reducing the torque of the car wheels by:
- Reducing fuel supply to the engine
- Retarding the ignition timing
- Closing the throttling valve for air intake
ABS vs Traction Control System
The main difference between ABS and Traction Control system (TCS) is that ABS stop the wheel from spinning when the brakes are applied while the traction control system stops the wheel from spinning while the vehicle is accelerating.
Traction control system consists of wheel speed sensors that continuously send signals of wheels speed to the engine control module. Other than that, both traction control anti-lock braking systems (ABS) have a common component called a “Hydraulic Unit” to apply brakes to the car wheels.
Stability Control System vs Traction Control System
The difference between the stability control system and the traction control is that the stability control system features more vehicular programming and more electronic sensors to monitor the wheel speed and their traction on slippery surfaces. Traction control system handles the front-to-back motion of the wheel, while the electronic stability control system (ECS) monitors the side-to-side motion of a vehicle around its vertical axis.
The stability control system uses a steering angle sensor in addition to a wheel speed sensor and ABS to measure the steering angle position and rate of turn along a path. In simple words, the steering angle sensor measures the direction the driver intends to aim the car.
Since a vehicle’s intended traveling path is detected by the stability control system, it is a more advanced way of controlling the traction of a vehicle in addition to just controlling the wheels’ speed.
Why Does Traction Control System Light Turn On the Dashboard?
The most common reason for which the traction light turns on the car dashboard is the malfunctioning wheel sensors. If the wheel speed sensor fails to send the signals to the engine control unit that the wheel is rotating abnormally fast, the engine control system would be unable to send the signals to the hydraulic unit (ABS) to slow down the wheel speed.
Proper diagnosis of traction control issues usually requires a specialized scan tool to find the trouble code that can help identify which component of the traction control system is causing the fault, due to which the traction control system light is turning on the car dashboard.
Sometimes, you will notice that both ABS and TCS lights will show up on the car dashboard. The reason is that your vehicle’s ABS and Traction Control System (TCS) often share the same control module. So, if a problem with one machine in the control module occurs, it will trigger the light for both ABS and TCS.
Causes of Traction Control Light Coming on Car Dashboard
Here are the causes of traction control lights coming on the car dashboard.
- Faulty wheel speed sensors
- Damaged wires of wheel speed sensors
- Low level of brake fluid (oil)
- Worn-out brake pads of ABS
- Bad steering angle sensors
- Bad condition of tires
- Less tire pressure
- Too bad road conditions
- ABS internal module failure (hydraulic pump, electric power motor are faulty)
- Programming issues of vehicle’s traction control module
How Does Bad Steering Angle Sensor Turn On the Traction Light?
A steering angle sensor is placed in the steering column of the vehicle that determines the optimal angle at which the car wheels should be turning.
The steering angle sensor of a vehicle works with the anti-lock braking system that keeps the oversteer or understeer from getting worse while slowing the car to a controllable speed. If the steering angle sensor fails to function properly, the car stability system will go haywire and send out signals which will cause the traction light to come on.
You can check out the short video below to understand why a bad steering angle sensor sends the error code.
Can You Still Drive With Traction Control Light On?
Yes, you can still drive with a traction control light on if the condition of your car’s tires is fine, the road surface is clean and dry, and your car is safely moving over the surface without skidding or slipping while accelerating or taking a turn. However, you should be aware that the traction light usually turns on when any component of traction control, ABS, or electronic stability system is damaged. So, you should get it fixed any issues with TCS, ABS, and ECS of your car because you will never know when you will need it.
Can Tire Pressure Affect Traction Control?
Yes, car tire pressure can affect traction control. When the tires are underinflated, they may not provide adequate traction for braking. If the tire pressure is too low, the tires will lose traction and slide on the road. This causes skidding and results in accidents.
Does Traction Control Have a Fuse?
Usually, cars have a fuse for the traction control system or ABS located in the fuse box. Each car has a different fuse box layout. So, you can locate the fuse for the traction control system, ABS or stability control system as all these safety features are interconnected.
As an example, I have attached the snapshot of the Honda Sonata Fuse Box Layout:
On the top right of the above image, you can see that TCS named fuse is the fuse for the traction control system.
Should I Turn Off Traction Control System?
If your car is stuck in deep snow or a bog, you can turn off the traction control system by simply pulling out the fuse. To get the car out of deep snow or a bog, the wheel of a car tends to spin fast to get your car out if it is stuck in a. deep snow. Since the traction system is designed to slow down the wheel speed to maintain traction, turning off the traction control system will allow your car’s tires to receive more power so that you can manage to get the car out of the snow.