BMW 640i Power Steering Pressure Switch Replacement at your home or office.

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.