Learn The Meaning Of ‘TC’ On Your Car
‘TC’ means traction control in your car. The traction control system in cars and trucks helps prevent wheel slippage and maintain control in low traction conditions. It uses sensors to monitor wheel speeds and automatically brakes individual slipping wheels to transfer engine torque to wheels with grip. This allows stable acceleration on wet, icy, or loose surfaces. If the electronic control unit detects a fault, it alerts the driver with a “Service Traction Control” message so that he can stop and fix the problem with tractional control system.
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.
What Is The Meaning of a Traction of Car Wheels?
The grip between a car’s tires and the road is called traction. Without traction, wheels would spin in place and go nowhere.
Traction depends on three key factors:
- Tire width – Wider tires increase contact with the road.
- Tire pressure – Proper inflation maximizes grip.
- Downward force – More weight enhances friction between rubber and asphalt.
As a mechanical engineer, I understand the physics behind traction. When the engine spins the wheels, they push backwards on the pavement. This creates an equal and opposite reaction force that pushes the tires forward – traction. Traction propels the vehicle down the road.
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?
Slippery roads? No problem for modern cars thanks to traction control systems! Let’s explore how these clever systems keep you gripping the road.
It all starts with wheel speed sensors attached to each tire. These sensors detect when a wheel spins significantly faster than the others, like when accelerating on an icy patch.
The sensors rapidly communicate with the car’s engine computer, known as the ECU (Engine Control Unit). The ECU analyzes the wheel speeds and decides if traction control is needed.
If so, it seamlessly taps into the ABS (Anti-Lock Braking System) to apply the brakes to the fast spinning wheel, slowing the vehicle and regaining control. This prevents dangerous overspinning.
For more stubborn traction issues, the ECU can also reduce engine power by limiting fuel intake, retarding ignition timing, and closing the throttle valve. This cuts torque to the wheels and further stabilizes the car.
The ABS contains a hydraulic control unit that enables all this. An electric motor drives a hydraulic pump which precisely modulates brake fluid pressure when needed. Solenoid valves rapidly open and close this flow per the ECU’s commands.
ABS vs Traction Control System Difference
The main difference between ABS and Traction Control is simple. ABS stops wheels from spinning when braking. Traction control stops wheels from spinning when accelerating.
Both systems use wheel speed sensors. These sensors constantly send wheel speed signals to the engine control module. ABS and traction control also share a hydraulic unit. This unit applies the brakes to the 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 has more programming and more electronic sensors to keep an eye on the wheel speed and traction on slippery roads.
The traction control system handles the front and back motion of the tires, while the electronic stability control system (ECS) watches the side-to-side motion of a car around its center line.
The stability control system uses a steering angle sensor plus a wheel speed sensor and ABS to measure the steering angle position and rate of turning along the path. In simple words, the steering angle sensor checks which way the driver is aiming the vehicle.
Since the stability control system can detect the direction a car is headed, it is a more advanced way of controlling traction in addition to just managing the wheels’ speed.
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 false 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 or pressing the button inside your vehicle.
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 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.