Linear EGR Control
WARNING: This page is about a different car, the 2011 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
The linear EGR valve is controlled by a high side driver within the engine control module (ECM). The high side driver provides 12 volts that is pulse width modulated (PWM) by a duty cycle via the high control circuit of the EGR valve . The ground path is provided by the low control circuit of the EGR valve. The ECM 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