Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the logical successor to CHARM, I recommend you try it!

Link: lemon-manuals.la

Air Flow Meter/Sensor: Testing and Inspection

MASS AIR FLOW SENSOR (MAFS)




FUNCTION AND OPERATION PRINCIPLE
Mass Air Flow Sensor (MAFS) is a hot-film type sensor and is located in between the air cleaner and the throttle body. It consists of a tube, a sensor assembly and honeycomb cell and detects intake air quantity flowing into the intake manifold. Air flows from the air cleaner assembly through the honeycomb cell and over the hot film element. At this time, heat transfer is generated by convection and this sensor loses its energy. This sensor detects the mass air flow by using the energy loss and transfers the information to the ECM by voltage. The ECM calculates fuel quantity and ignition timing.

Specification:




SPECIFICATION

Circuit Diagram:




CIRCUIT DIAGRAM