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Home >> Cadillac >> 2000 >> Catera >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 3.0L >> Diagnostic Tests >> DTC P0602: Control Module Not Programmed >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Flash ECM with correct software. New ECM must be programmed with theft deterrent module frequency code currently on vehicle. If DTC resets, go to next step. If DTC does not reset, go to step  5 .
  3. Verify that equipment being used is functioning properly and that all cable connections are clean and tight. Attempt to flash ECM again. If DTC P0602 resets, go to next step. If DTC P0602 does not reset, go to step  5 .
  4. Replace ECM, then go to step  2 .
  5. Using scan tool, clear DTCs. Turn ignition off for 15 seconds. Start engine and operate vehicle. Check for DTCs. If DTC P0602 is set, go to step  2 . If DTC P0602 is not set, go to next step.
  6. If other DTCs were present during OBD system check and have not been diagnosed, go to applicable DTC. If no other DTCs are present, system is okay.
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