Operation CHARM: Car repair manuals for everyone.

General Description

The Powertrain Control Module (PCM) controls most components with electronic switches which complete a ground circuit when turned ON. These switches are arranged in groups of 4 and 7, and are called either a surface mounted quad driver module, which can independently control up to 4 outputs (PCM) terminals or an output driver module, which can independently control up to 7 outputs. Not all outputs are always used.