LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Hummer >> 2003 >> H2 >> Repair and Diagnosis (Single Page) >> Engine Performance >> Theory and Operation >> Engine Controls - Theory & Operation - Gasoline >> Computerized Engine Controls >> Powertrain Control Module
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Powertrain Control Module

The PCM has a "learning" ability which allows it to make minor corrections for fuel system variations. PCM is located on left front of engine compartment, behind radiator. See Fig 1. If battery power is interrupted, a vehicle performance change may be noticed. PCM module corrects itself, and normal performance returns if vehicle is allowed to "relearn" optimum control conditions. "Relearning" occurs when vehicle is driven at normal operating temperature under part throttle, moderate acceleration and idle conditions.

Fig 1: Locating PCM
G00169499Courtesy of GENERAL MOTORS CORP.