Power Steering Pressure Sensor

What is a Power Steering Pressure Sensor and where is it Located?

The power steering pressure sensor, also referred to as a power steering pressure switch, gives your vehicle’s computer information about the demand being placed on the power steering system. The power steering system uses hydraulic pressure generated by a pump which is driven by the crankshaft via a belt. Demand on the power steering system puts a demand on the engine. The engine must speed up when you are turning at low speeds like when you are parking your car or truck. If that didn’t happen, then the engine might stutter or stall. 

The power steering pressure sensor contains a diaphragm that activates a switch. A spring pushes against the diaphragm. Fluid from the power steering lines can press on the diaphragm. When the pressure on the diaphragm overcomes the spring, the diaphragm presses the switch, which signals the computer that there is high demand on the power steering system. In response the computer can speed up the engine so that the power steering pump can work more effectively.  

In terms of location, you will be able to find the power steering pressure switch by following the lines from the car or truck’s power steering pump to the steering rack or steering gearbox. The pressure sensor will be attached to the line near the rack or gearbox.

How do I Know if my Power Steering Pressure Sensor Needs to be Replaced?

The power steering pressure sensor can wear out over time due to the high pressures it is exposed to. If this happens, then the computer will not be able to respond to increased demand on the power steering system. If your power steering pressure sensor isn’t working, you may find that the engine slows down when you try to turn the wheel while moving at low speed or at idle. In some cases the engine may stall or it may slow down and then speed up as the computer overcompensates. If the computer recognizes that the power steering pressure sensor has become stuck in an always-on or always-off position, then the check engine light will come on. When a bad sensor has triggered the check engine light, a mechanic with a diagnostic scan tool can identify power steering pressure sensor failure as code P0551, as can a basic OBD2 scan tool.

Can I Replace a Power Steering Pressure Switch Myself?

Fortunately, the power steering pressure switch will prove relatively easy to replace. You can find it by following the lines from the power steering pump to the steering rack or steering gearbox. You will find the pressure sensor attached to the line near the rack or gearbox. Before you remove it, you’ll want to drain the fluid from the power steering fluid reservoir. Then you can disconnect the wiring harness from the old sensor and remove it from the power steering line. Then insert and connect the new one and add power steering fluid as necessary. Upon installation, you can the test the system by trying some turning maneuvers at low speed.  You'll want to try and get any air out of the lines that were drained, usually by turning the wheels from one extreme to the next a few times.  You will also want to check for any leaks to make sure the switch has been properly installed.

Need a Power Steering Pressure Switch Replacement?

The power steering pressure switch's function is to tell the vehicle’s computer when the power steering system exceeds it normal operating hydraulic pressure. If the pressure is exceeded, the computer will raise the idle speed of the engine to prevent it from stalling. If the switch is not working, it won’t be able to give the computer this important information, the computer will not be able to respond to the increased demand on the power steering system, and you will have some problems on your hands. So, be sure to replace your power steering pressure sensor as soon as possible if it is not working properly. At 1A Auto, we carry a large selection of aftermarket power steering pressure switches for many makes and models, and at great prices.

At 1A Auto, we make shopping for a replacement power steering pressure sensor for your car, truck, SUV, or van easy - we're here to help you select the right part for your vehicle! Call our customer service toll free at 888-844-3393 if you have any questions about our power steering pressure switch replacements, warranty, compatibility or to purchase, or you can buy online.