Pressure Sensors

Designed to detect, monitor or regulate many of the functions or performance of your vehicle a pressure sensor will send electrical signals to the engine control module to advise on changes such as when the pressure drops or when outside of a fixed pressure. When these sensors measure pressure they can activate the ECU to perform specific functions. This would be the case in common rail diesel vehicles that rely on a fuel rail pressure sensor to advise of sufficient fuel pressure. When low pressure is encountered the electrical signal from the sensor will trigger the fuel pump to increase flow rates via the ECU.

In tandem with a host of faults or vehicle gremlins that may be encountered one of the easiest ways to identify an issue is via the check engine warning light that may become illuminated on the dashboard. While this won't give you any specifics of the sensor at fault or where the problem lies it will provide the necessary warning of problems.

From there it always pays to use a scan tool in situations such as this, as replacing sensors when not faulty can be expensive and unnecessary. A decent quality scan tool will be able to provide the fault code and from there you can gain further information on any error codes by researching online.

Another method is to use a multimeter to measure the electrical resistance from the sensor. This output or measurement will advise if the sensor is faulty if reading outside the voltage range for that sensor.