Unlike traditional hydraulic power steering, electric power steering (EPS) does not require fluid. Here’s an overview of how EPS differs:
How Electric Power Steering Works
EPS uses an electric motor to provide power assist for turning the wheels:
- Sensors detect the amount of steering effort and direction applied by the driver.
- A computer module processes this data and commands the electric motor to apply the appropriate assist.
- The electric motor connects directly to the steering gear or column, not a hydraulic system.
No Hydraulic Fluid
Since EPS relies on electrical components rather than hydraulics, no power steering fluid is used in the system:
- There is no hydraulic pump, hoses, or reservoir that must be filled with fluid.
- The electric motor provides assistance directly rather than operating a hydraulic pump.
- Without fluid, there is no risk of leaks that could lead to loss of power assist.
Maintenance Benefits
The lack of fluid simplifies maintenance and repairs:
- No need to regularly check power steering fluid level or condition.
- No flushing or replacement of deteriorated fluid is required.
- Less environmental impact as there is no fluid waste or leakage.
- System is more reliable overall with fewer points of potential failure.
So in summary, electric power steering eliminates the need for hydraulic fluid by using an electric motor to provide assist. This simplifies maintenance while improving reliability.
Frequently Asked Questions
Do you still need to service EPS systems?
Yes, the electrical components and connections should be inspected regularly. But there are no fluid checks or changes needed.
What happens if the EPS motor fails?
You will lose power steering assist. The vehicle can still be steered manually but it will require more effort.
Do all electric cars have EPS?
Most do. EPS provides appropriate assist levels while reducing load on the battery compared to hydraulic systems.
Does EPS affect steering feel?
EPS programming is tuned to provide natural steering feel comparable to hydraulic systems. Some early systems felt artificial but this has improved greatly.