Electronic Control Systems
Accident prevention systems increase safety
Electronic control systems (ECS) assist the driver in maintaining traction and control of the vehicle. Computerized systems analyze the current situation and make adjustments and compensations to help prevent accidents. Driver skill, reaction time & tire condition are the foundation of how well these systems function.
Currently, there are several systems that dominate the market. Refer to your owner’s manual if you are unsure of what system(s) your vehicle has. These systems can work in a variety of ways so know what particulars your ECS systems have. Vehicles may come equipped with none, all or a combination of these systems.
Sometimes, these systems can lull drivers into a false sense of security. This technology can lead a driver into believing that these systems can compensate for almost any situation they enter. This is not true. Do not drive beyond the system and vehicle limitations. Electronic control systems are designed to assist, not create miracles or overcome the laws of physics.
This article is not meant to make you a mechanic, only to inform you of some basics of these systems so you can better be prepared in an emergency situation. The effectiveness of the following electronic control systems depend on if the computer and the sensors are working correctly. If any warning devices activate, indicating the system is not working or in need of maintenance, ensure you follow through and take it into your mechanic immediately.
Never forget, the foundation of how well these systems work is dependent on human factors and responsibilities: Driver Skill Reaction Time Tire Condition
Anti-lock braking System or ABS
This system is linked to the braking system.
The basic principle: When your vehicle is in a skid, you lose steering ability as the steering tires are no longer rotating preventing steering from occurring. With ABS you maintain steering as the wheels are prevented from locking-up or skidding. Each wheel is controlled individually to prevent a skid. Due to this, the ABS system will also give the vehicle a smoother, straighter stop and help maintain the vehicle's stability in an emergency situation. This is especially noticeable on slippery or icy surfaces were 1 or 2 wheels can skid while the others are still rotating.
Computer sensors watch each wheel to help prevent lock-up by watching and releasing the wheel(s) before lock-up occurs. When the ABS is activated, the computer will “pulse” brake pressure to each wheel that has slowed down to help you stay in control of the vehicle. This maintains steering control and maximises braking ability.
A common misconception about ABS is that you can stop with a shorter braking distance; this is not always the case. Usually it’s the same approximate stopping distance but, you maintain steering allowing you to steer around hazards. In most cases, steering to the right is better, to avoid on-coming traffic.
Steering is maintained - Steer where you want to go!
Years ago we handled emergency braking situations different. Without ABS, when we locked-up the brakes and were in a skid, we had no steering. A common mistake people still make is they react the same way they did before they had a vehicle with ABS. When the ABS is activated, it can be a natural reaction to turn the wheel to the left spinning the vehicle around to hit the obstacle on the passenger side. If we do this now when we have ABS, the vehicle maintains steering ability and we can steer into oncoming traffic. We need to re-train ourselves if we have not previously driven with ABS. We need to realize steering ability is maintained and this gives you the ability to steer around obstacles.
A possible benefit to non-ABS equipped vehicles: May stop slightly better on loose gravel or snow due to the loose material wedging in front of the tires. This may be a small benefit to drivers that use their vehicle off-roading recreationally. Over all, the everyday benefits ABS provide far outweigh this one aspect of non-ABS braking systems.
Don’t pump the brakes!
Emergency Braking with an ABS Braking System
Emergency Threshold Braking (No ABS braking system on your vehicle)
Brake Assist
This system is linked to the braking system.
Vehicles that have Brake Assist also have ABS.
A computer analyzing system designed to assist the ABS system during sudden or “panic” braking or slippery road conditions. It adds full pressure to the brakes to help prevent a collision. During sudden braking, reaction time can be shortened. A driver may not apply enough pressure to the brake pedal. Brake Assist sensors will detect this and apply additional pressure to compensate.
This is very helpful for sudden problems that may occur. Sometimes we are day dreaming and not paying as much attention as we should and an event happens suddenly in front of us. Another great instance is when you are travelling at highway speeds and an animal jumps out onto the road right in front of you. Maybe traffic ahead has come to an abrupt stop without notice. Maybe a pedestrian steps out in front of you.
This technology has averted many accidents and saved thousands of lives. Studies done by Mercedes-Benz revealed that 90 % of drivers failed to brake with enough force in emergency situations.
Additionally, some systems take into account how fast you release the fuel pedal. With the urgency of the fuel pedal release, the system senses that it is possibly an emergency situation and prepares the braking system to assist.
Traction Control System or TCS
A.K.A. Anti-slip Regulation (ASR)
This system is linked to the accelerator and braking system.
Vehicles that have TCS also have ABS.
This computerized system prevents the wheels from spinning during acceleration. On slippery, icy or uneven surfaces, this system helps maintain traction. It senses a speed difference between the drive wheels & the vehicles speed. If the computer analyzes a problem, it applies the brake on the wheel(s) that is spinning and reduces the engines power helping to prevent loss of control.
Can be advantageous to turn off during 2 situations:
Electronic Stability Control or ESC
A.K.A. Roll Stability control (RSC)
This system is linked to the steering wheel and braking system.
Vehicles that have ESC also have the ABS.
A computer helps minimize skids by using the ABS system. It applies the brakes to individual wheels aiding in steering control. This system improves safety through vehicles stability by detecting and minimizing skids. This can be helpful when spinouts and fishtailing on tight curves might occur and on slippery or icy surfaces. Also, when you are swerving to avoid an obstacle, this system will help prevent the vehicle from rolling over.
When the ESC detects a loss of steering control, it applies the brake(s) to help regain steering control allowing the driver to go where they intended to. This system monitors your steering angle and the direction your vehicle is actually traveling and senses when your front or rear wheels begin to slip.
Front wheel slip can occur when the front wheels lose traction during cornering and begin to drift toward the outside of the turn.
Rear wheel slip can occur when the rear wheels lose traction and cause the vehicle to slide around.
Braking is automatically applied to an individual wheel(s), such as the outer front wheel to counter the oversteering (when the car turns by more than the driver commanded) or the inner rear wheel to counter the understeering (the car steers less or under the amount commanded by the driver).
Some ESC systems also reduce engine power until control is regained.
A common misconception of the ESC System is that it improves a vehicle's cornering performance; instead, it helps to minimize the loss of control.
Can be advantageous to turn off during 2 situations:
Electronic Braking Force Distribution or EBFD
A.K.A. Electronic Brakeforce Limitation (EBL) or Electronic Brake Assist (EBA)
This system is linked to the braking system.
Vehicles that have EBFD also have the ABS.
A computer varies the amount of force applied to each brake based on road conditions (slippery or dry pavement), speed and weight distribution. It applies more or less braking pressure to individual wheels. This is to maximize stopping power on an instant-by-instant basis, while maintaining vehicle control. EBFD is a good system because it can increase the vehicle’s ability to stop under multiple conditions.
For example:
