Electric power steering is becoming more common in newer cars. However, this system is also prone to failure and can leave you stranded on the side of the road. This article will discuss the symptoms of electric power steering failure, causes of failures, and possible fixes.
The most common symptom of electric power steering failure is a feeling of loss of power assist while driving. Other symptoms may include unusual noise from the power steering motor or the vehicle pulling to one side while driving.
Table of Contents
What is an Electric Power Steering System?
Electric power steering (EPS) is a vehicle steering system that uses an electric motor to assist the driver in turning the wheels. This system replaces the traditional hydraulic power steering system, which uses hydraulic fluid to help the driver. EPS is a newer technology that offers several advantages over hydraulic power steering, including improved fuel efficiency and reduced emissions.
Plus, it is more reliable as there are fewer chances of failure due to a lesser number of working components. For example, there is no power steering pump or fluid leaks. Also, you would not need to worry about the power steering fluid levels. EPS is not without its disadvantages, it can be more expensive to repair or replace than a traditional power steering system.
Basic Working Principle and Sensors of an EPS System
An electric power steering system uses an electric motor to assist the driver when turning the steering wheel. The motor is connected to the steering column and interacts with the rack-and-pinion or recirculating ball-type steering gear to assist. When the driver turns the steering wheel, the electric motor provides a boost or assist that makes it easier to turn. Here comes the function of two of the most important sensors in the EPS system.
1. Torque Sensor:
The torque sensor determines the amount of assistance provided by the electric motor. The torque sensor measures the force the driver exerts on the steering wheel and sends a signal to the electronic control unit (ECU). The ECU then determines how much assistance to provide from the electric motor.
2. Speed Sensor:
The function of the speed sensor is to measure the wheels’ rotating speed and send a signal to the ECU. The ECU uses this information and input from the torque sensor to determine how much assistance to provide from the electric motor. Some cars employ a separate steering angle sensor to measure the angle of steering as well.
Hazards of Driving With a Failed Electric Power Steering Systems
If the EPS system fails while driving, it will become more difficult to steer the vehicle. This can make it difficult to keep the car in its lane and may even cause the vehicle to veer off course. In some cases, the car may even become disabled entirely.
If you find yourself in this situation, it is important to remain calm and avoid panicking. Try to keep the vehicle under control as best as you can and slowly bring it to a stop. Once the vehicle is stopped, turn on the hazard lights and call for roadside assistance. Do not attempt to drive the vehicle if the EPS system has failed. Doing so could put you and others at risk of serious injury or even death.
Symptoms of Electric Power Steering Failure
Several symptoms can indicate that the EPS system is failing. The most common symptoms include:
- EPS Warning Light
- Loss of Power Assist
- Vehicle Pulling to One Direction
- Whining Noise From Power Steering Motor
- Soft Steering Wheel at High Speed
- Vibrations From Steering Rack
Let us see these symptoms in detail:
1. EPS Warning Light:
If your electric power steering system fails, it can trigger an EPS warning light on your dash. This light is usually red or yellow, meaning there is a problem with your power steering. If you see this light, you should take your car to a mechanic to have it checked out.
2. Loss of Power Assist:
If the EPS system fails, you will lose power assist. This means that it will become more difficult to turn the steering wheel. The loss of power assist can be sudden or gradual. If it is sudden, it can be very dangerous as it can make it difficult to keep the vehicle under control.
If you lose power assist gradually, you may not notice it at first. However, over time, it will become more and more difficult to turn the steering wheel. This can make driving long distances very tiring.
3. Vehicle Pulling to One Direction:
If your electric power steering system fails, the vehicle may start to pull to one side. This can be very dangerous as it can make it difficult to keep the vehicle in its lane. The root cause of this problem is typically a malfunctioning sensor or defective power steering motor.
When either of these components fails, they can provide more assistance in turning the vehicle to one side than the other. As a result, the vehicle will begin to pull in that direction.
4. Whining Noise From Power Steering Motor:
If there are power steering issues, you may hear a whining noise from the power steering motor. This noise is caused by the gears inside the motor grinding against each other. The noise will become louder as the EPS system starts to fail.
In this case, the motor cannot generate the necessary torque to turn the wheels. The electric power steering system may also fail to provide adequate assistance if the motor is not properly sized for the vehicle.
5. Soft Steering Wheel at High Speed:
If you notice that the steering wheel is softer than usual at high speeds, it could be a sign that the EPS system is failing. The electric power steering offers the ability to adjust the level of assistance based on driving conditions. For example, more assistance may be provided at lower speeds when it is more difficult to turn the steering wheel, and less assistance may be provided at higher speeds when it is easier to turn the steering wheel.
So, at higher speeds, the steering should become really hard and very soft at slower speeds. However, if the EPS system fails, it may provide unnecessary assistance even at higher speeds. As a result, you may feel the steering wheel slipping.
6. Vibrations From Steering Rack:
If you notice any vibration in the steering wheel, it is important to have it checked out by a mechanic as soon as possible. The electric power steering system uses a rack and pinion to convert the rotational motion of the steering wheel into linear motion. This linear motion is used to turn the wheels of the vehicle. If the rack and pinion are not properly aligned, it can cause vibration in the steering wheel.
In addition, if there is excessive play in the rack and pinion, it can also cause vibration. The root cause of this problem is typically a worn-out or damaged rack and pinion.
What Causes Failure of Electric Power Steering?
There are four main causes of electric power steering failure:
1. Control Unit Issues:
When it comes to electric power steering (EPS) system failures, control unit issues are often to blame. The control unit is the “brain” of the EPS system, and it’s responsible for interpreting sensor data and sending commands to the motor. If there’s a problem with the control unit, it can cause the EPS system to fail.
Control unit issues can lead to EPS system failure because the control unit may not be properly calibrated. If it’s not calibrated correctly, it may not be able to interpret sensor data correctly. This can lead to the EPS system providing incorrect information to the motor, which can cause the EPS system to fail.
2. Driving on Rough Terrains:
Another common cause of EPS system failure is driving on rough terrains. When you drive on rough terrains, the EPS system must work harder to stabilize the vehicle. This can put a lot of stress on the components of the EPS system, which can lead to component wear and tear. The system may be unable to handle the bumps and vibrations of driving on rough terrain, which can lead to failure.
In addition, when you drive on rough terrains, there is a risk of the EPS system being damaged by debris. If a rock or other object hits the EPS system, it can damage the steering rack or other critical components.
3. Malfunctioning Sensors:
The EPS system relies on sensors to gather data about the vehicle’s speed, steering angle, and other factors. If any of these sensors are not working properly, it can cause the EPS system to fail. Sometimes, the sensor may be damaged and need to be replaced. In other cases, the sensor may need to be recalibrated.
4. Electric Motor Failure:
The electric motor is one of the most important components of the EPS system. If the electric motor fails, it can cause the EPS system to fail. There are a few reasons why an electric motor may fail. One reason is that the brushes in the motor may wear out. The brushes are responsible for transferring electrical current to the rotor. If they wear out, they can no longer transfer electrical current.
Another reason why an electric motor may fail is that the bearings in the motor may wear out. The bearings support the rotor and allow it to spin. If the bearings wear out, the rotor can’t spin, which can also cause the motor to fail.
How to Fix Electric Power Steering Problems?
Unlike conventional hydraulic steering systems, no steering pump or fluid needs to be replaced. So in order to fix issues with the electric power steering system, you will require an altogether different strategy. Here are some tips on how you can fix electric power steering problems.
1. Scan for Any Error:
The first thing you need to do is connect a scan tool to the vehicle’s diagnostic port. This will help you in checking for any error codes that the power steering system has logged. If there are any error codes, note them before proceeding further.
2. Check the Wiring:
Once you have noted the error codes (if any), the next step is to check the wiring of the power steering system. Inspect all the wires and connectors for any signs of damage or wear and tear. If you find anything amiss, make sure to repair or replace the damaged parts.
3. Check if Power Steering Motor is Working:
If nothing seems wrong, then probably the power steering motor is to blame. To be certain, follow these steps:
- Start your Vehicle.
- Let it run for a few minutes.
- When you turn the steering wheel while idling, this is the time when the highest level of power assistance is required.
- The power steering motor should come on immediately to provide that assistance.
- You might not be able to hear the hissing sound of the motor with an automotive stethoscope.
- Try placing a stethoscope under the steering wheel near the rack. That is where the sound should be apparent.
- So, with the help of an automotive stethoscope, you can try to listen to the sound of a power steering motor while turning the steering wheel.
- If you cannot do both things together, maybe you can use the help of a friend.
Fixing Cost of Failed Electric Power Steering System
The cost of fixing a failed electric power steering system can be quite high. In some cases, it may even cost more than the price of the entire steering system. The most common problem that occurs with the electric power steering system is the failure of the electric motor.
The cost to replace the electric motor varies between $350 and $500. The other common problems may be related to sensors or control unit malfunction. In which case, you will need to pay hefty sums to skilled mechanics. To resolve the error codes. The cost of such a procedure may range between $200 and $300.
The electric power steering system is an important safety feature in modern automobiles. It allows the driver to maintain control of the vehicle while turning and provide additional assistance when needed, such as during emergency maneuvers. It can help prevent accidents by making it easier to steer. The driver can keep the car in their lane and avoid potential hazards. This can be especially helpful in slippery conditions or if the road is unexpectedly uneven.
However, electric power steering systems are also prone to failure. If your electric power steering system fails, it can be expensive to fix. Therefore, it is important to be aware of the symptoms of electric power steering failure and to have a plan in place in case your system does fail.
Frequently Asked Questions
Does electric power steering light mean low power steering fluid levels?
There are no fluids in the electric power steering system, so there is no question that the EPS warning would light up due to this reason. The electric power steering light is usually an indication that there is a problem with the electric power steering system. It does not necessarily mean that the power steering fluid levels are low.
What is a common cause of electric power steering failure?
There are a few common causes of electric power steering failure. One is a problem with the electric motor. Another is a problem with the control unit. And another is a problem with the sensors.
Is electric power steering powered by a car battery?
Yes, an electric power steering motor is powered by a car battery. So, if the battery power is low or you have a weak battery, you will likely experience a lack of assistance while steering. The power steering motor needs a specific amount of electric power for normal operation. If the battery does not provide this power, the car may have difficulty steering.
Can you make adjustments to an electric power steering system?
Yes, it is possible to adjust an electric power steering system. You can adjust the level of assistance it provides while steering as well as the extent to which it will provide that assistance.
Additionally, you can also toggle certain features on and off, such as the return-to-center function. Ultimately, the adjustability will depend on the specific model and make of your electric power steering system.
What are the differences between electric and hydraulic power steering?
There are a few key differences between electric and hydraulic power steering. Hydraulic power steering uses fluid pressure to turn the wheels, while electric power steering uses an electric motor to assist. Electric power steering is typically more efficient than hydraulic power steering and often provides a smoother, more responsive feel when driving. Additionally, electric power steering generally requires less maintenance than hydraulic power steering.