A power steering system is designed to utilize power from the engine or an electric motor to assist in the force needed to steer a vehicle which is achieved by a steering box or rack. EV's will have an electric steering rack that may or may not be attached to the steering wheel, a sensor and control unit give the steering rack commands via the position of the steering wheel. We will address hydraulic based systems first and then move onto electrically assisted systems.
There is a fair amount of force involved when steering a vehicle, an electrical motor or a hydraulic assist system can wear or fail completely creating a difficult situation when controlling the car. This can be due to a fluid leak, pump or electric motor failure which typically is accompanied by an abnormal noise. It is advised NOT to move a vehicle with the power steering system not operating or the engine not running, you may lose control of the vehicle. Sometimes the steering system is not the problem, if you lose power steering and the battery warning light comes on it means the serpentine belt of the engine has fallen off.
When steering your vehicle, if there is a low grinding or gurgling sound the
first inspection is to
check the power steering
fluid level, if the fluid is low the pump will be weak and make noise as it
scavenges for fluid. Check the power steering fluid level by locating the power
steering fluid reservoir and removing the cap (twist counter clockwise). Some systems
have a fluid level dipstick mounted inside the cap while others are present on the
side of the fluid reservoir, if the fluid level is down or empty the system has
a leak. Using a flashlight the system should be inspected for leaks.
A popular failure for power steering system leaks and non operation is the high
side power steering hose, use a flashlight to inspect the hose, the failure will
be obvious, if leaking or blown the
steering hose will need
to be replaced.
If the the system is full and the belt is on the pump but it still has no power
steering chances are there is no pressure being produced and the
power steering pump needs
to be replaced.
If your car has power steering in one direction but not the other this means
the power steering rack and pinion, or
steering box needs to be replaced.
EV's and some conventional gasoline vehicles are equipped with an electronic
steering system which can be assisted with an electrical motor or completely electrical
(no shaft connecting the steering wheel to the rack). In either case, the system
can malfunction due to a blown fuse,
sensor or main controller failure, or electrical motor can wear or short out completely.
If a failure occurs and the fuses are okay, a
regular code scan will be needed. If no codes are present a more in-depth
CAN scan (controller
area network) to identify the problem. Below is an example of what an electric steering
rack looks like.
Our certified technicians are ready to answer power steering questions for free. We hope you saved money and learned from this guide. We are creating a full set of car repair guides. Please subscribe to our 2CarPros YouTube channel and check back often for new videos which are uploaded regularly.