AA Car Care: Power Plays

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EPS is a must-have in newer cars to enable driver assist technologies to function. Photo / Supplied

EPS is a must-have in newer cars to enable driver assist technologies to function. Photo / Supplied

The benefits of electronic power steering and its relationships with safety devices

Electronic power steering (EPS) has become an everyday feature in today's vehicles.

Traditionally, car buyers have been faced with two options when it comes to the choice of power steering -- electronic or hydraulic. Both have been available for many years, but EPS has become more common and we receive a lot of inquiries from members wanting to know how it all works.

EPS explained

EPS typically uses a conventional rack and pinion set up. It's controlled by the vehicle's computer -- and information from the steering sensors is received by the computer to determine the amount of assistance needed by the driver.

The electronic motor, which is coupled to the rack or steering column, helps the driver to steer the vehicle when parking and cornering.

EPS vs hydraulic power steering

Before EPS was introduced, hydraulic power steering was the most common form of assisted steering.

Though some used vehicles still have this system, it is not without its shortcomings.

Over a period of time, hydraulic components can start to leak.

Because it relies on fluids that need to be changed, hydraulic power steering will require more servicing than EPS systems. The hydraulic pumps in this steering system also continuously run, so contribute towards additional fuel costs.

Unlike hydraulic power steering, EPS offers potential fuel savings as the electric current is used only when required.

On a straight direct route, there is little load on the engine (great for cars with a small engine) as more focus can be placed on acceleration.

EPS and Lane Keep Assist

Though there are many pros that come with owning a car with EPS, in many cases -- particularly in the new car market -- it's a must-have because driver assist technologies wouldn't be able to function without it.

Vehicles in today's market are commonly equipped with Lane Keep Assist (LKA), but did you know information from the EPS system is what helps this to function?

Information is shared between the two systems contributing to small adjustments to the steering that help the driver remain in their lane.

EPS and Electronic Stability Control

ESC is another safety system that uses information gathered from the EPS. Where the driver has lost control of the vehicle, ESC collects information from the steering angle and torque sensors to apply the brake and throttle, in order to help the driver to regain control of the vehicle.

It becomes easy to understand why EPS is overtaking hydraulic power steering. What started out as a more efficient way to save on fuel and reduce engine loads, has now become a necessity in some vehicles to allow safety technologies to function.

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