Powertrain Control Module Location
WARNING: This page is about a different car, the 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, 2003 Chevrolet Monte Carlo, and 2003 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
On Alero & Grand Am, the PCM is located below the instrument panel, next to the Data Link Connector (DLC). On Impala & Monte Carlo, the PCM is located in Left side of the engine compartment, forward of the strut tower, inside the air filter box.