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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 P0603: Control Module Long Term Memory Reset >> 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. If DTC P1621 is also set, go to step  4. If DTC P1621 is not also set, go to next step.
  3. Ensure ignition is on. Using scan tool, clear DTCs. Monitor SPECIFIC DTC INFO for this DTC. If DTC runs and passes, no problem is indicated at this time. Fault may be intermittent. If DTC resets, go to next step.
  4. Replace PCM. Program replacement PCM. See PROGRAMMING .
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