Many more of new cars and trucks today are using a new kind of power steering system. This system is all electric. That is, there is no hydraulic power steering pump that is driven by the engine drive belt. No fluid to build pressure to operate the rack and pinion. No power assist of any kind from fluid. There is not fluid reservoir to check and fill, and thus no chance of it ever having a fluid leak. Conventional power steering uses a belt driven pump to direct high pressure to the rack and pinion or gearbox. The force you put on the steering wheel is enhanced by this pressure to allow for easy turning of the wheel, even when the vehicle is not moving. When the vehicle is moving, it is easier to steer, even without any power assist from hydraulics or an electric motor.
All of the power assist for the electronic steering is generated by an electric motor. This motor is under the dash on most vehicles. It connects the steering wheel and column to what is called the intermediate steering shaft. This shaft is driven by the electric steering motor, then sends steering assist to the rack and pinion. This is all controlled by a module or computer. Here is a pic of a typical steering motor…
General Motors had a few problems in this new system a few years ago. What would happen is that your car would loose power assist. Your car would not lose steering, just the power assist portion. So that would make the steering wheel hard to turn. Similar to what happens if you ever had a belt break or had very low fluid on your vehicle in the past. Many people complained they lost steering, could not turn the car, and almost crashed. I do understand that a sudden loss of power assist can be very disconcerting, but you do still have control of your vehicle. You just need to use a little more effort to turn it.
There has been a lot of chatter on the web about this problem. Many forum posts have people talking about how they fixed it by replacing the fuse. Well, if the fuse was not blown, then replacing it would do nothing to help and did not fix the problem except for a short time. Removing the fuse basically takes power away from the control module. This has the effect of resetting the system. Just as if you unplug your computer, then turn it back on. The steering problem will just return soon enough.
There have been problems with the system in other cars as well. Toyota, BMW and Lexus, among others have all had some problems ranging from bad steering motors to control modules. This is actually a common thing to happen as a new technology enters the market and gets real life testing from the consumer.
The auto manufacturers all do extensive research and testing before putting a new technology in their vehicles. The problem here is that no matter how much testing and simulating is done, it still does not compare to real world driving by the every day person. So problems do arise.
Another thing that effects this sort of thing is mass manufacturing. A product is tested on a small sample of the different parts to a certain system, but until the factory that builds the parts starts producing millions at a time, you never know what may happen. Anything from a bad batch of steel or plastic, to a programming glitch or a factory that just plain had a bad day with it’s machines. Auto parts are made by machines, which in turn were made by people or other machines.
If you have a newer vehicle with electric power steering and a warning light comes on the dash, be sure to get it to the dealer for repairs as soon as possible. Most small local repair shops do not have the knowledge or diagnostic tools to diagnose a problem correctly, and you may end up spending a lot of extra money on parts replacing, or best guesses. Many times that local shop will replace what they think is most likely the problem, then after you pay hundreds of dollars you are told to “Take it to the Dealer” even after you have paid them. Now when you go to the new car dealer and the repair is more money, you get mad at the dealer for charging so much. When in reality if you went there first, you would have saved all the money you threw away at the local repair shop !