Circuit Description

PCM controls movement of EGR valve using the EGR control circuit. PCM monitors pintle position input to ensure that valve responds to commands from PCM. When ignition is on, PCM learns an EGR closed valve pintle position. When PCM commands valve closed, PCM compares the learned closed EGR pintle position to actual EGR position. DTC will set when actual EGR position indicates an open valve when PCM has commanded valve closed.

Conditions for setting DTC:

• System voltage greater than 11 volts.
• DTC P0401 inactive.
• EGR is enabled.
• EGR position less than 20 percent.