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.

PCM detects engine misfire by detecting variations in crankshaft speed. For accurate detection of engine misfire, PCM must be able to distinguish between crankshaft deceleration caused by actual misfire or deceleration caused by rough road conditions.

ABS system can detect if vehicle is on a rough road based on wheel acceleration/deceleration data supplied by each wheel speed sensor. If ABS system detects a rough road that is rougher than a predetermined threshold, this information is sent to PCM via Class 2 serial data circuit. PCM can then take rough roads into account when calculating misfire. DTC P1380 is set when ABS system is not capable of detecting a rough road situation.

When DTC sets, PCM will not illuminate MIL. PCM will store conditions resent when DTC set as failure records data only. A history DTC is set.

A history DTC will clear after 40 consecutive warm-up cycles without a fault being detected. DTC can be cleared with a scan tool.