Saturday, March 1, 2014
How to Test an Air Mass Meter
Air mass meters, more commonly known as mass air flow sensors or MAF sensors, are devices used in vehicle engines. They are used to determine and measure the amount of air that flows into a vehicles engine. A hot wire element provides information to the vehicles on-board computer on the air flowing into the engine by becoming cooler when more air enters the engine. However, the MAF sensor can become faulty over time and provide wrong information to the on-board computer. You can check your MAF sensor regularly by performing a few tests to determine if it is functional.
Instructions
MAF Sensor Test
- 1
Park the vehicle on a flat surface. Turn off both the ignition and the vehicles engine. In many vehicles, turning the key in the ignition once will power the vehicles battery. This allows the user to control electrically-powered devices such as the radio. Turning the key further will power the engine to start the vehicle. In this case, turn the ignition and the engine off. Disconnect and remove the electrical connector on the MAF sensor.
2Connect the ohmmeters positive probe on the MAF sensor terminal that is marked as "SIG".
3Join the negative probe on the ohmmeter to the "GND" terminal on the MAF sensor.
4Record the reading from the ohmmeter. If the reading indicates an infinite resistance or open circuit, the hot wire element of the MAF sensor is damaged.
Power Supply Test
- 5
Park the vehicle and turn on the vehicles ignition. Do not start the vehicles engine but ensure that the ignition is on.
6Open the vehicles hood. Determine the location of the MAF sensor and its electrical connector. Generally the sensor is located on the intake duct on the air filter housing in the front portion of the engine.
7Disconnect the MAF sensors electrical connectors. Join the voltmeters negative probe to the sensors GND terminal and the positive probe to the terminal indicated as "B+".
8Record the voltage on the sensor. A voltage reading of zero indicates the MAF sensor may not be receiving any or enough electrical input from the vehicles on-board computer, which means the MAF sensor is not functioning properly. There should generally be a steady fluctuation in the voltage if the MAF sensor is functional.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.