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Home >> Chevrolet >> 2002 >> Venture Plus >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (Engine Control System - Self-Diagnostics - 4.6L) >> Diagnostic Tests >> DTC P1621: Powertrain Control Module Memory Performance >> Diagnostic Procedures
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Diagnostic Procedures

WARNING: This page is about a different car, the 2001 Cadillac Seville, 2001 Cadillac Eldorado, and 2001 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
  1. If powertrain diagnostic system check has already been performed, go to next step. If powertrain diagnostic system check has not been performed, go to POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  2. Replace PCM. Program replacement PCM. See PROGRAMMING . After repairs, go to POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.