How to Check My Car's Power Steering Fluid?

The power steering system is a crucial component of your vehicle, making it easier to turn the steering wheel and maintain control of your car. To ensure that this system operates smoothly, regularly checking the power steering fluid is important. Low or dirty fluid can cause your steering to become stiff or unresponsive, and in some cases, it could lead to more serious issues.

Steps to Check Power Steering Fluid

Maintaining the correct power steering fluid level is essential for smooth and responsive steering. Here's a step-by-step guide to help you check your power steering fluid:

1. Prepare the Vehicle

• Warm Up the Engine: Start your vehicle and allow it to idle until it reaches its normal operating temperature. This ensures the fluid is at the proper temperature for an accurate reading.
• Turn the Steering Wheel: Rotate the steering wheel fully to the left and right a few times. This helps circulate the fluid, providing a more accurate measurement.

2. Locate the Fluid Reservoir

• Open the hood and find the power steering fluid reservoir. It's usually a small, transparent container with a cap labeled "Power Steering Fluid." Check your vehicle's manual for the exact location if you're unsure.

3. Check the Fluid Level

• Transparent Reservoirs: Many vehicles have a transparent reservoir with "MIN" and "MAX" lines on the side. Ensure the fluid level is between these two markers. You'll need to add more fluid if it's below the "MIN" line.
• Dipstick-Equipped Reservoirs: If your vehicle uses a dipstick, remove the cap and wipe the dipstick clean. Insert it again, then remove it to check the fluid level. The dipstick may have "COLD" and "HOT" or "MIN" and "MAX" indicators to guide you.

4. Inspect the Fluid Condition

Healthy power steering fluid is usually clear or light amber. If it appears dark, murky or smells burnt, it's time to replace it. Regularly changing old fluid helps prevent damage to the pump and ensures optimal steering performance.

5. Add Fluid if Necessary

If the fluid level is low, top it up with the recommended power steering fluid. Be careful not to overfill, as fluid can expand when heated and may spill out.

6. Final Steps

• Securely replace the cap after adding fluid.
• Start the engine and turn the steering wheel from lock to lock a few times to help the new fluid circulate.
• Recheck the fluid level and top it up if needed.

Regularly checking and maintaining your power steering fluid helps keep your vehicle’s steering system running smoothly and extends its lifespan. Always consult your owner's manual for specific recommendations on fluid types and maintenance intervals.

Differences Between Electronic Power Steering (EPS) and Conventional Hydraulic Power Steering

Electronic Power Steering (EPS) systems and traditional hydraulic power steering systems are two different types of power steering technology, and their operating principles, components, advantages and disadvantages, and maintenance requirements are very different.

1. Working Principle

Electronic Power Steering (EPS):

• Electric Drive: The EPS system uses an electric motor to provide power assistance. The electric motor is connected to the steering shaft and the amount of power assist is regulated by an electric current and control module. The electric motor automatically adjusts the level of assistance according to the driver's steering effort and vehicle speed.
• Electronic Control: The EPS system monitors the driver's steering needs and vehicle dynamics in real time through electronic sensors and control units. It provides precise power assistance according to different driving conditions.

Hydraulic Power Steering (HPS)

• Hydraulically driven: HPS systems rely on an engine-driven hydraulic pump to power the steering system. Hydraulic fluid flows through pipes to the steering gears or steering pump to provide assistance to the driver.
• Mechanically controlled: Hydraulic power steering systems have no electronic controls. The amount of power-assisted is determined primarily by the pressure of the hydraulic pump and engine speed, and there is usually no ability to automatically adjust the amount of power-assisted based on driving conditions.

2. Components

Electronic Power Steering (EPS):

• Electric motor: Provides direct power assist to the steering.
• Sensors and Control Module: Used to monitor and regulate steering assistance.
• Batteries and Circuits: The system relies on electrical power for actuation.
• Steering Shaft or Gear: Connects to the electric motor and transmits power assistance.

Hydraulic Power Steering (HPS):

• Hydraulic Pump: Driven by the engine to provide pressure to the hydraulic system.
• Hydraulic Lines and Reservoir: Used to transfer and store hydraulic fluid.
• Steering Gear and Boost Pump: Converts the pressure of the hydraulic fluid into boost.
• Relief valve: used to regulate the flow of hydraulic fluid to prevent damage from excessive pressure.

3. Advantages and Disadvantages

Electronic Power Steering (EPS):

Pros:

• Energy saving: the electric power system does not rely on the engine, reducing the burden on the engine and improving fuel efficiency.
• Precise control: Electronic control automatically adjusts the amount of power assist according to vehicle speed, steering angle and other factors, providing a more precise steering feel.
• Less maintenance: There are no mechanical parts such as hydraulic pumps and pipes, reducing the possibility of oil leaks and hydraulic system failures.
• Lighter weight: lighter than hydraulic systems, especially advantageous in electric and hybrid vehicles.

Disadvantages:

• Higher complexity: EPS systems contain more electronic components, which can require complex electronic diagnostic tools and higher repair costs if a failure occurs.
• Higher cost: Due to the complexity of electronic control systems, manufacturing costs are relatively high.

Hydraulic Power Steering (HPS):

Pros:

• Mature technology: Hydraulic systems have been in use for many years and are technologically mature, making repairs and maintenance relatively simple.
• High Power Assist: At low speeds, the hydraulic system can provide stronger steering assistance.

Disadvantages:

• High energy consumption: the hydraulic pump is driven by the engine, resulting in increased load on the engine and reduced fuel efficiency.
• Susceptible to oil leakage: the hydraulic system is susceptible to oil leakage, resulting in reduced system efficiency or even damage.
• Frequent maintenance: the hydraulic system requires regular checking of the hydraulic oil level and fluid replacement.

4. Maintenance and Repair

Electronic Power Steering (EPS):

• Since the EPS system consists mainly of electronic components and an electric motor, maintenance frequency is low. However, in the event of a malfunction (e.g., motor damage, sensor failure, etc.), repair may be more complicated and expensive.
• Common problems: motor failure, control module failure, inaccurate sensors, etc.

Hydraulic Power Steering (HPS):

• The hydraulic system requires regular inspection and replacement of the hydraulic fluid to avoid insufficient or contaminated fluid. Hydraulic pumps and piping systems may also suffer from wear or leaks and need to be inspected regularly.
• Common problems: hydraulic fluid leakage, pump damage, fluid contamination, etc.

5. Applicability

Electronic Power Steering (EPS):

Suitable for modern vehicles, especially electric vehicles (EVs) and hybrid electric vehicles (HEVs). More and more modern vehicles are using EPS systems due to their high energy efficiency, low weight and better regulation of the power assist.

Hydraulic Power Steering (HPS):

Widely used in conventional vehicles, especially older models. Although modern vehicles are more likely to use EPS, some high-performance models and large-displacement vehicles still use hydraulic power steering because it provides a stronger and more consistent sense of assistance.

Regularly checking your power steering fluid is a straightforward yet essential task to ensure your vehicle's steering system operates smoothly. By maintaining the appropriate fluid levels and monitoring its condition, you can prevent potential steering issues and avoid costly repairs down the line.
Remember to consult your vehicle's owner's manual for specific instructions and recommended maintenance schedules. If you notice any abnormalities, such as unusual noises when turning the wheel or difficulty steering, it's advisable to have your vehicle inspected by a professional mechanic promptly.