Variable Assist Power Steering has been most researched and engineered for the last two decades among all the latest features. Years of intense research gave rise to a perfect blend of the old and new technology that can help to make the engine more efficient.
Finally, in 1951, Chrysler was the first person to invent power-assisted steering, and soon other manufacturers adopted this technology.
Currently, this technology is being employed on numerous vehicles, but do you know how to tell if you have variable-assist power steering?
If you want to figure out the presence of a variable-assist power steering in a vehicle, then the following steps can help you determine.
#Look up your car serial number at the dealer.
First, you must analyze the type of power steering system present in your vehicle. Do not miss looking at the vehicle specifications from the seller or online over a specific website.
Generally, it is expected to know if your vehicle has variable power assist or not from the vehicle specifications. However, it is crucial not to get confused between vehicle specification and variable ratio.
#Look at your Service Parts Identification label.
To identify a variable-assist power steering, you may try doing a visual search. You can start that by studying the hydraulic power assist if that uses a droop flow pump. If this pump stays in the same place even with an accelerated engine RPM, that means your vehicle is aided with variable-assist power steering.
Furthermore, try checking out the area that remains under the lid of the trunk. If you find codes like 1SC, you are most likely to have gm variable-assist power steering.
Last but not least, you can also check the area underneath your spare tire case. If you notice any code similar to NV7, the Service Parts Identification label, then be sure that your car has variable-assist power steering.
#Understand your kind of power steering system
After identifying your variable-assist power steering system in your vehicle, let’s know the types of the power steering system. The most common types of assists include-
- Hydraulic assist– In a Hydraulic Power steering, the system uses a pressurized power steering fluid powered by the steering pump. The hydraulic mechanism checks the steering effort. As a result, the winding belt signals high-pressure power steering fluid to the gear and controls the valve. You must check out the force of the steering wheel to understand if that is a Hydraulic-assisted power steering system. The force only befalls from the high hydraulic system remains the same irrespective of the speed.
- Electric-assist– In the electric-assist system, the brushless bi-directional permanent magnet motor remains connected to the steering gear. The magnetic motor rotates or turns the front wheels as the driver turns the steering wheel. To this action, the sensor detects which way the steering wheel is turning and immediately assists the movement of the steering gear in the required direction.
There is no doubt that variable-assist power steering is one of the most efficient technologies used in vehicles.
How does variable-assist power steering work?
The variable-assist power steering works flawlessly by regulating the pressure of the steering gear.
With this technology, the sensor tracks the speed and rotation of the car’s wheel and indicates the control unit. The unit regulates the pressure that reduces the flow of fluid into the steering gear system.
As a result, lesser fluid flow increases the stability and prevents the car from running out of control.
Diagnosing the mechanism
The advanced system utilizes the vehicle’s speed and pressure to assist the steering at varied speed (as high as running through a highway or as low as while parking a car).
A specially designed system controller keeps track of the sensors’ speed and pressure-related data. To pump up the fluid to the steering valve, the system controller indicates the variable-assist steering actuator.
This particular action impacts the pressure exerted on the steering valve. As we already know, the steering valve is responsible for controlling the rack piston mechanism. The rack piston is responsible for altering the anterior portion of the vehicle wheels and is required to steer the car.
Electronic Variable Orifice or the EVO
Electronic Variable Orifice or the EVO is one of the most crucial components in the variable-assist system. At speed below 40 MPH, the EVO opens up, enabling maximum power to pump up the hydraulic fluid from the power steering to the steering unit.
Now when the speed exceeds its limit, a specially designed control module stimulates the EVO to restrict the flow of the hydraulic fluid.
Therefore, the intelligent mechanism of reduced assist enhances stability. The variable-assist power steering also ensures lesser risk by providing better control at such a high speed.
To ensure better functioning of the variable-assist power steering, the EVO valve, control module and vehicle speed sensors must be in good working condition.
In the worst-case, if any of these components does not work accurately, the regulated assist mechanism will not work. As a consequence, the vehicle will even lose the power assist steering ability.
Variable assist power steering system is an incredible technology and one of the most reliable options. However, the only drawback is that it may start wearing down after using it for a long time. Once it starts to wear down, it may end up passing out wrong signals to the control unit.
Active steering vs Variable assist steering
Active steering is one of the most advanced operations used in a vehicle. The primary function of it is to control the driver’s steer information with steer angle. In most cases, you can find active steering on heavy-duty vehicles and in some BMW passenger cars.
The technology reduces the power electric variable gear ratio to turn the steering wheel at the minimum speed. This decrease in ratio enhances the performance while you park your car or drive at a low speed. The technology in response to higher speed ensures stability and avoids speed jerks.
On the contrary, it may seem the mechanism of Variable -assist steering is similar to active steering. Variable-assist technology is one of the best blends of fingertip parking at lower speed and reduced assistance at higher speed. The mechanism ensures a smoother feel and higher stability.
Is the variable ratio different assist steering ?
Yes! There is no doubt that variable-ratio is not similar to assist steering.
The former is an electronically controlled variable gear ratio that adjusts to the ideal steering condition irrespective of the car’s speed. This variable ratio adjusts the shape of the teeth on the frame.
When space reduces, the teeth at the rack’s centre move up, and the intermediate space increases as the pinion move down the rack. Therefore, the variable steering ratio mechanism can only be beneficial only if assist steering accompanies it.