Powertrain Control Module (PCM) — removal and installation
Caution: To avoid electrostatic discharge damage to the PCM, handle the PCM only by its case. Do not touch the electrical terminals during removal and installation. If available, ground yourself to the vehicle with an anti-static ground strap, available at computer supply stores.
Note: The PCM is mounted in the left front corner of the engine compartment.
Note: The procedures in this section apply only to disconnecting, removing and installing the PCM that is already installed in your vehicle. If, however, you need to replace the PCM, it must be programmed with new software and calibrations. This procedure requires the use of GM’s TECH-2 scan tool and GM’s latest PCM-programming software, so you WILL NOT BE ABLE TO REPLACE THE PCM AT HOME.
1. Disconnect the cable from the negative terminal of the battery (see Engine electrical systems).
2. Unplug the electrical connectors from the PCM (see illustration). To unlock each PCM electrical connector, slide the red lock out, then depress it while swinging open the connector lever.
14.2 PCM mounting details
1 Connector lock
2 Connector lever
3 PCM upper mounting tabs
3. Disengage the retaining tabs that secure the PCM to its mounting bracket and remove the PCM.
4. Installation is the reverse of removal.