Power steering is an advancement that we all have come to rely on. There are some issues that can arise with these modern machines, especially when they get older.
If you see a Dashboard Indicator popping up or if you are having difficulty controlling your vehicle, you’ll want to understand how to fix a power steering assist fault. You don’t want to drive your vehicle with these issues, of course.
In this guide, we explain what the power steering assist system does and what components could be failing. We also highlight the repair process for fixing the system once you have identified the problem. Finally, we review estimated costs of repairs, based on what might need to be serviced.
What does the Power Steering Assist Fault Message mean?
The Power Steering Assist Fault message means that there is a fault in your electrical or mechanical power steering system. The fix could be as simple as adding power steering fluid or repairing electrical faults, but you may also have a more serious fault.
Most cars use electric power steering these days and most often when you see this warning message, there is a fault within this unit or one of its sensors. So let’s look at the system in more detail.
What Is Power Steering Assist?
In the 1950s, steering any vehicle required considerable effort to get it to go where you wanted it. Power steering first appeared in domestic cars in 1951 and the very first vehicle whose model to receive that feature was the Chrysler Imperial.
The power steering system has evolved since then, now incorporating electric power assisted steering systems. While it still has liquid to supply pressure and able to turn it, the old style systems took energy from the engine and the power steering system. Using an electric pump, the steering process is simplified.
The hydraulic fluid is usually located in a reservoir, and as the steering wheel is moved, fluid is transferred through the system displacing liquid and creating the positive force to do the work of turning the car wheels. Older systems had a belt from the engine to provide energy to the pump. Most newer vehicles have an electric pump powered by the battery-like hydbrid vehicles.
Today’s advanced safety features use the power steering to function, so it’s very important to be in good working order. If your vehicle uses any parallel park assist, lane assist or advanced technology, your car’s power steering system is probably playing a role in that process.
Causes of Power Steering Assist Fault
#1. Low Fluid.
Hydraulic and electrical power steering systems involve fluid for proper operation. If the steering fluid isn’t topped off, this is where problems may arise. Typically, if you experience low fluid, you will be implementing more effort to turn the vehicle.
You also want to be mindful of what caused the fluid to be low in the first place to avoid further issues. If there is a leak you will want to fix that before refilling the system. Otherwise, you will have leaked fluid again or could end up losing power steering altogether.
You should also change the power steering fluid at regular intervals. Check the owners manual to see how often.
#2. Bad steering angle sensor.
For the power steering to work correctly, it needs to know “where” your steering wheel is angled or if it is straight. The vehicle will accomplish this through a steering angle sensor located behind the steering wheel.
If this sensor fails and provides the wrong angle, it will trigger a power steering assist error message. It’s not uncommon for you to have problems with vehicle traction control or other important behaviors due to this issue as well.
#3. Bad Wheel alignment.
Very poor wheel alignment can trick the computer into thinking the steering angle sensor is bad, which will turn on the power steering assist error message.
If you’re driving your car at a higher speed, and the steering wheel is not straight, or your car is pulling to one side, then you have a wheel alignment issue.
#4. Blown fuse.
It may be something simple, such as a fuse that has blown for the power steering pump or some separate power steering circuit. While fuses should not blow with nothing wrong, maybe it has blown due to a sudden voltage spike it may have just gotten fit.
Look at your owner’s manual for where the power steering fuses are located in your automobile.
#5. Electrical Fault.
Electrical problems are always a possibility, especially if you have power steering that’s newer. If you checked the fluid level, then this would be your next step if everything else checks out.
You might have a weak battery. Again, if you have a warning light on the dashboard, use your code scanner for hunting down the problem. You might want to check the wiring and connectors that make up the steering system as well. Anything could go wrong after all of those years.
#6. Failing Belt.
If your car uses a traditional power steering setup where a belt runs from the engine to provide power to the power steering, then that’s a potential source of problems.
If you hear a weird noise when turning it’s probably a bad power steering belt.
#7. Bad Power Steering Pump.
While the traditional and electrical power steering systems have pumps, they work differently. If the pump goes bad, the fluid can’t flow through the system.
In both cases, the pump itself is the least likely part to fail, though it isn’t impossible. If checking other causes hasn’t yielded anything else, it might be time to consider the pump.
How to Fix a Power Steering Assist Fault
#1. Add Fluid.
It’s important to regularly check the level of power steering fluid and to add some when needed. The system shouldn’t lose any fluid, but it is a good idea to verify.
If you see a lot of fluid has been lost, just fill it back up and determine where it went. If you find leaks, it is best to let your mechanic deal with them.
Most car makers recommend changing the power steering fluid every four years or 50,000 miles, whichever comes first. If you fail to change it, the fluid will get contaminated and, as a result, will no longer do its job.
#2. Check trouble codes.
Before troubleshooting electrical issues in your vehicle, you should always start by getting the fault codes with an OBD2 scanner; reading fault codes can be very useful and, in some cases, won’t cost you anything.
If a power steering assist fault shows on you dashboard, then there is a fault code, that is what identifies why the light is on. You may go to a repair workshop to have them read the fault code, or get an OBD2 scanner to read it yourself.
It’s important to get a scanner that fits your car model’s power steering assist system.
#3. Get a wheel alignment.
If you scan the trouble codes and there is a problem with the steering angle sensor, you might want to check the wheel alignment first. If you have an OBD2 scanner, such as an owner’s model, you can check the steering angle values directly from the sensor.
If those values seem correct and your steering wheel is not straight while driving at higher speeds, you might want to get a wheel alignment.
#4. Replace Steering angle sensor.
If the wheel alignment appears fine, but there are still error codes for your steering angle sensor, you may need to replace it. Most vehicles will involve removing the steering wheel to access it.
In some vehicles, you may need to program the new steering angle sensor, and frequently, it can only be done by a dealer.
#5. Repair Electrical Fault.
Figuring out an electrical problem is not always easy; there are a lot of wires and connections to look at if you are going to find the problem. I would suggest starting with the fuse because it may have blown.
If that is not the issue, move into everything else electrical in the system. If you see any connectors or wires that are frayed or damaged, then it may be time to replace them.
#6. Replace Failing Belt.
If the problem is due to a belt-driven system, you may need a replacement. This can be easy in some models.
However, there are many models that make it difficult to change the belt. If you aren’t sure what you are doing, go to a professional before anything else gets messed up.
#7. Replace Power Steering Pump.
Replacing a power steering pump is a big hassle for most people, but this part can also fail. If the diagnostics take you to the pump, then you just need to switch the part out.
Check your service manual for the full process for replacing the pump on your vehicle. If that sounds too complicated, then take it to a local auto repair shop.
Cost to Fix a Power Steering Assist Fault
The cost of repairing your power steering assist fault can range from $5 to $550 or higher, depending on the troubleshooting report. If you only need to top up a little fluid, or possibly just replace a fuse, then the repair cost would be very low.
Repairing leaks, electrical issues, or the replacement of major components can cause the bill to rise significantly. Cars that are luxury models are almost always more expensive to repair because of the extra expense in specific replacement parts, but also because a specific type of mechanic will be required for repair of the system.
Doing the repairs yourself will help to keep the bill down considerably. However, do not attempt to work on the hydraulic or electric power steering system if you are unsure of what you are doing. One simple mistake can lead to a very expensive repair bill.
What is the cost to fix a power steering assist fault?
The cost to fix a power assist steering fault varies, costing between $0 and $1000, with no fixed cost. Luckily, you may be able to fix the issue by replacing a fuse or adding power steering fluid for no more than $10.
If you are not so lucky, the repair costs could be much more if the source of the problem is caused by bad power steering pump which could cost $1000 or more on the upper range.
Can I drive with a power steering assist fault?
While it is possible to still drive a car with no power assist steering fault, it is not recommended. The handling of your vehicle becomes difficult and unsafe and depending on the severity, you may not be able to steer the vehicle safely to avoid an accident.
What is the advantage of power assist steering?
Power assist steering, or power steering, is a function in your car that is designed to make it easier for the driver to steer the steering wheel of your car.
It uses a hydraulic pump to produce a force on the steering wheel to assist with the steering motion which will assist easier steering to help maneuver your car.
How can I tell if my power-assist steering is functioning?
If you do not see any power steering warning indicators or messages showing in the drivers dashboard, with the steering wheel operating smooth and easy to turn, you power steering is likely functioning properly.