What is the Power Steering Pressure Switch all about?

Power steering makes steering a vehicle much easier at low speeds. However, because the system is powered by the engine, increased loads can cause problems. The harder the power steering system must work to meet the demands of the driver, the heavier the load is placed on the engine.

The power steering pressure switch is located either at the power steering pump or the gearbox. It’s an on/off type of switch that communicates with the vehicle’s computer by sending information about the fluid pressure in the system, and if necessary, the computer adjusts the engine’s operation to account for increased demand. In some systems, the switch is also tied into the vehicle’s air conditioning and will turn off the compressor at certain load points (or communicate with the ECM to turn off the compressor). The switch uses a diaphragm, as well as two electrical sensors. Over time and through exposure to heat, the sensor can malfunction or fail.

Keep in mind:

• The power steering pressure switch is not part of any regular maintenance.
• The power steering pressure switch cannot be inspected without significant teardown.
• Failure of the power steering pressure switch can mimic a number of other problems with the system, so it’s vital that one of our expert mechanics diagnose the problem.

How it's done:

• The hood is opened and the engine is allowed to cool then drained of fluid
• The power steering pressure switch is removed from the pressure line
• The new power steering pressure switch is installed into the pressure line
• The power steering system is refilled with fluid and purged of air
• The engine is run and the power steering system operation is checked

Our recommendation:

The power steering system of your vehicle makes handling at low speeds much easier. It’s an important part of your vehicle, and if you’ve noticed that it isn’t operating correctly, we recommend having one of our expert mechanics diagnose it.

What common symptoms indicate you may need to replace the Power Steering Pressure Switch?

• Lack of power steering assist
• Engine stutters under heavy steering load

How important is this service?

While it’s not as critical as your drivetrain, the power steering system does offer vital usability enhancements. We recommend having any malfunction diagnosed as soon as possible by one of our expert mechanics. Note that problems with the pressure switch can be similar to numerous other issues, so self-diagnosing the failure is not recommended.