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Home >> Chevrolet >> 2001 >> Chevy Express G3500, Van Cargo Extended, 6.5 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 6.5L >> Diagnostic Tests >> DTC P0606: Control Module Internal Performance >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Check DTCs. If DTC P0602 is set, go to next step. If DTC P0602 is not set, go to step  5.
  3. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After reprogramming PCM, check for DTCs. If this DTC resets, go to next step. If this DTC does not reset, go to step  6.
  4. Ensure that all tool connections are secure. Ensure programming equipment is operating correctly and correct software/calibration package is used. Attempt to program PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. Recheck DTCs. If this DTC resets, go to next step. If this DTC does not reset, go to step  6.
  5. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  6. Turn ignition on, with engine off. Using scan tool, clear DTCs. Start and warm engine to normal operating temperature. Select DTC, SPECIFIC, and then enter this DTC. Operate vehicle within FREEZE FRAME conditions. If scan tool indicates that this test ran and passed, go to next step. If scan tool does not indicate that this test ran and passed, go to step  2.
  7. Using scan tool, check for DTCs. If any undiagnosed DTCs are set, perform appropriate DTC test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are set, system is okay.
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