Linear EGR Control

The linear exhaust gas recirculation (EGR) valve is controlled by a high side driver within the powertrain control module (PCM). This high side driver uses a 12-volt pulse width modulated (PWM) signal. The ground path for the EGR valve is completed by turning on a separate driver within the PCM. The PCM calculates the amount of EGR needed based on the following inputs:

• The engine coolant temperature (ECT) sensor
• The intake air temperature (IAT) sensor
• The barometric pressure (BARO)
• The manifold absolute pressure (MAP) sensor
• The throttle position (TP) sensor
• The mass air flow (MAF) sensor