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Home >> Buick >> 1996 >> Roadmaster Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Systems - Tests W/Codes >> Diagnostic Trouble Codes >> DTC P0602 - Pcm Not Programmed >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) System Check. After performing OBD system check, go to next step.
  2. Flash PCM with current software. If DTC is reset, go to next step. If DTC does not reset, go to step 5).
  3. Verify that test equipment used is operating properly and that all connections are clean and tight. Attempt to flash PCM again. If DTC resets, go to next step. If DTC does not reset, go to step 5).
  4. Replace PCM. Program replacement PCM using required equipment. After repair is completed, go to next step.
  5. Using scan tool, select DTC, CLEAR INFO function. Start and warm engine to normal operating temperature. Select DTC, SPECIFIC, then enter DTC P0602. Operate vehicle within conditions for setting this DTC. If scan tool indicates that this test ran and passed, go to next step. If scan tool did not indicate that this test ran and passed, repeat step 2).
  6. Using scan tool, select CAPTURE INFO, REVIEW INFO function. If any undiagnosed DTC(s) are displayed, go to applicable DTC test.
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