Power Assisted Steering, or ‘PAS' as it is also known, is a mechanism that helps you to steer your car. In most vehicles, the PAS relies on a hydraulic system to aid turning the vehicle's wheels. If you have ever driven a car with no Power Steering you will have most certainly noticed the difference between having PAS and not. Power Steering used to be a luxury in certain vehicles, but nowadays it is almost standard in every type of vehicle.
In the early days of the automotive industry, power-assisted steering was a luxury and was only available in high-end vehicles. Most new cars now have it as standard. That’s because they’ve become heavier, with wider tyres and front wheel drive, and would be extremely difficult to drive without PAS. This makes a car not only more pleasant to drive, but safer to drive too.
There are two types of hydraulic power-assisted steering: rack & pinion and the recirculating ball. Rack & pinion is the most common. The recirculating ball is far less common and only really exists in vans and trucks. Both have high-pressure hoses that connect the steering rack to the two sides of the centre seal. One hose sends hydraulic fluid from the power-steering pump to the steering mechanism, while the other directs fluid back to the pump. When turned left or right, the steering wheel’s steering mechanism allows the hydraulic fluid to pass to respective side of the steering rack, pushing the seal and rack in the necessary direction.
Electric power-assisted steering is fully electric. The wheels of the car receive direct assistance from an electric motor which is mounted on either the steering rack or steering column or directly to the steering rack. Sensors decide how much assistance to apply at any time.
When hydraulic fluid lubricates and seals the power-steering pump and hoses to prevent corrosion it can leak or gradually become less effective, making it harder to turn the steering wheel. Typically, a mechanic will check hydraulic fluid levels during an annual service.
If the electric motor fails, power-assisted steering will stop working, so the motor would need replacing. As with any electrical system, software problems can occur, necessitating an update.
Find a trusted, local garage to carry out a power steering repair for you at Book My Garage or call one of our expert mechanics on 03304 004439 to discuss the problem and help you choose the best garage to do the job.