Incorrect Pcm Programming

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2003 GMC Sonoma, 2003 GMC Safari, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.

There are only a few situations when reprogramming a PCM is appropriate, such as the following:
- A new service PCM is installed.
- A PCM from another vehicle is installed.
- Revised software or calibration files have been released for this vehicle.

NOTE: DO NOT reprogram the PCM with the SAME software or calibration files that are already present in the PCM. This is not an effective repair for any type of driveability problem.

Verify that the PCM contains the correct software or calibration. If incorrect programming is found, reprogram the PCM with the most current software or calibration. See POWERTRAIN CONTROL MODULE under PROGRAMMING in SELF-DIAGNOSTICS - 4.3L ASTRO, BLAZER, JIMMY CANADIAN, SAFARI, SONOMA & S10 PICKUP article.