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Home >> Cadillac >> 2001 >> Seville SLS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Self-Diagnostics - 4.6L >> Diagnostic Tests >> DTC P1621: Powertrain Control Module Memory Performance >> Diagnostic Procedures
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Diagnostic Procedures

  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.
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