Let’s explore how to test the oil pressure sensor with a multimeter and how it works. Oil is an essential element of any vehicle to keep it in running condition. The importance of oil in any vehicle can be considered as blood in the human body. Therefore, there is a need for the condition, and its flow should be properly checked and maintained regularly.
As we described earlier, oil is important as blood, so the vehicle engine has the value of a heart in the body. Whenever we have any issue in our blood, it disturbs the whole body; the same as if the vehicle oil has any problem, it disturbs the vehicle’s performance, and it can be caused to shorten the engine’s life.
Bad oil, thick oil, low supply of oil, and oversupply of oil all these issues can damage your vehicle’s performance and its life. Therefore, the oil pressure should be kept under observation. Every vehicle installs a mechanical oil pressure switch with an oil pressure sensor.
What is Oil Pressure Switch and Sensor?
An oil pressure switch is a part that controls the oil flow, and it has a sensor with a light, which indicates if there is any issue with the vehicle’s oil or its pressure.
An on/off switch is installed in the vehicle’s oil filter box, valve cover, and engine box. The sensor controls the oil flow, and its light turns on if the oil pressure drops from its required level.
What is a Multimeter?
A multimeter is a device used for testing the oil pressure of the vehicle through its oil pressure switch and its sensors. It is an electrical device, and its testing depends upon the types of oil pressure switches and sensors. Usually, oil pressure switches and sensors are available in types of One, Two, and Three pins, and their testing method is also different.
These switches and sensors also depend upon the types/categories of the vehicles. We will discuss all three methods of testing the oil pressure of all switches, but first, we will discuss the standard procedure for testing the oil pressure.
Testing Oil Pressure Sensor with Multimeter
There are three main steps to test the oil pressure sensor with a multimeter.
Turn off the engine
To start the test, you must switch off the engine and disconnect it from the vehicle. Still, it is pertinent to mention that you remove the vehicle cables from battery terminals; removing the battery from the vehicle is not required.
With the engine off, test the resistance
Now, first of all, set the multimeter at the required level of pressure. Then attach one wire of the multimeter with the warning light sensor and attach the second wire to the box in which the switch is installed (like the oil filter box, valve cover, and vehicle’s engine box).
You will get the reading at the multimeter’s display as you attach both wires. It will show 0 ohms on the meter’s screen if it works normally. After that, connect the wire to the oil pressure-sending unit of the engine. It should show that the circuit is currently open.
With Engine On, test the resistance
Now the final step is to check the resistance with the active engine. Firstly, you should attach the vehicle cables to the battery and start the engine. After that, attach the multimeter wires as described.
If the sensor is functional and oil pressure is also sent from the engine, the multimeter will show an infinity value on the display. It indicates that the circuit is open as well.
Testing of Oil Pressure with Different Types of Switches
Now we will discuss the different types of switches. As we described earlier that there are three types of switches
- Oil Pressure Switch with One Pin
- Oil Pressure Switch Two Pin Switch
- Oil Pressure Switch Three Pin Switch
Oil Pressure Switch with One Pin
The process is simple for the one-pin switch test; you have to connect the multimeter between the pressure sensor body and the pin. The circuit opens when the engine is in the running position and closes when the engine is switched off.
Oil Pressure Switch Two Pin Switch
For two pin switch, the process will be the same as one pin switch, but there is a need to understand that in the case of one pin switch, its body works as an earth connection, but in two pins, it doesn’t apply as it already has two pins.
So the testing process will be the same, and you should connect the multimeter between both pins. And the same rule applies that the circuit gets open when the engine is active and will be closed when the engine gets off.
Oil Pressure Switch Three Pin Switch
The three pins switch test is a bit complicated compared to the one or two- pin switch test. In this case, the switch has three pins. Therefore, one pin will perform as open, the second one will be closed, and the third will be neutral. It is very important that you know precisely about the pins, which one is open and which is closed, and the third should be ground.
Now for the testing, you should connect the multimeter between the expected open and closed pin. The same conclusion will be observed: the circuit will be open when the engine is active and closed when it gets off.