Theory Of Operation

WARNING: This page is about a different car, the 2020 Jeep Renegade. However, it is still accessible from the selected car via links, so may be relevant.

The Manifold Absolute Pressure (MAP) Sensor and the Charge Air Cooler (CAC) Air Temperature Sensor are combined into one component. The MAP Sensor is a typical 3-wire pressure sensor using a 5-volt reference circuit, a dedicated signal circuit, and a shared sensor ground circuit. The CAC Air Temp Sensor is a typical 2-wire temperature sensor that uses a dedicated signal and shared sensor ground circuit.

The MAP Sensor uses a transducer that varies in resistance according to changes in altitude and atmospheric conditions. When the engine is running, the PCM monitors the voltage on the signal circuit which is converted into a current air pressure and uses this to detect the air pressure within the Intake Manifold.

The CAC Air Temperature Sensor uses a thermistor which is a thermally sensitive resistor that varies in resistance according to changes in temperature. The PCM monitors the voltage on the signal circuit which is converted into a temperature reading and uses this to detect the temperature of the air entering the Intake Manifold.

NOTE:

Do not use shop air to clean out the MAP Sensor when diagnosing a MAP Sensor related fault as this will cause internal damage to the sensor.