Circuit Description

WARNING: This page is about a different car, the 2002 Isuzu Rodeo Sport and 2002 Isuzu Rodeo. However, it is still accessible from the selected car via links, so may be relevant.

EGR system is used to reduce NOx (oxides of nitrogen) levels. This system uses a linear EGR valve, designed to accurately supply exhaust gas to engine without using intake manifold supplied vacuum. Using inputs from various sensors, PCM controls EGR pintle position and can be monitored with scan tool. Actual EGR position should always be near commanded or desired EGR position. If PCM detects a continuous short to ground in signal circuit, DTC P0406 will be set.

When DTC sets, PCM illuminates MIL as soon as fault was detected. PCM will store conditions present when DTC was set. A history DTC is set, and EGR valve is disabled.

PCM will turn MIL off on third consecutive trip cycle during which diagnostic runs and fault is no longer recognized. DTC can be cleared with scan tool, or by disconnecting battery voltage feed to PCM.