Swift L4-1298cc 1.3L SOHC MFI (1997)
Manifold Absolute Pressure (MAP) Sensor: Description and Operation
This sensor senses pressure change in the intake manifold and converts it into voltage change. It consists of a semi-conductor type pressure
converting element which converts a pressure change into an electrical change and an electronic circuit which amplifies and corrects the electric
change. The ECM sends a 5-volt reference voltage to the pressure sensor. As the manifold pressure changes, the electrical resistance of the sensor
also changes. By monitoring the sensor output voltage, ECM knows the manifold pressure (intake air volume). ECM uses the voltage signal from
the pressure sensor as one of the signals to control fuel injector, shift-up indicator light, EVAP canister purge valve and EGR solenoid vacuum
valve.
