Function And Operation Principle

Fig 1: Identifying Manifold Absolute Pressure Sensor Location

Courtesy of KIA MOTORS AMERICA, INC.

Manifold Absolute Pressure Sensor (MAPS) is speed-density type sensor and is installed on the surge tank. This MAPS senses absolute pressure in surge tank and transfers this analog signal proportional to the pressure to the PCM. The PCM calculates the intake air quantity and engine speed based on this signal. This MAPS consists of piezo-electric element and hybrid IC that amplifies the element output signal. The element is silicon diaphragm type and adapts pressure sensitive variable resistor effect of semiconductor. 100% vacuum and the manifold pressure applies to both sides of it respectively. The sensor outputs the silicon variation proportional to pressure change by voltage.