LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Pontiac >> 1999 >> Sunfire L4-2.2L VIN 4 >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Description and Operation >> General Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

General Description




The Powertrain Control Module (PCM), located under the instrument panel, is the control center of the fuel injection system. It constantly looks at the information from various sensors, and controls the systems that affect emission or engine performance. The PCM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the Malfunction Indicator Lamp (MIL), and store a DTC or DTCs which identify the problem areas to aid the technician in making repairs.