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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 377 (Engine Controls - Self-Diagnostics - 4.3L) >> Diagnostic Tests >> DTC P0103: MAF Sensor Circuit - High Frequency >> Diagnostic Procedures

Diagnostic Procedures

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  1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Observe the Freeze Frame/Failure Records data for this DTC. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. See CONDITIONS FOR RUNNING DTC . Does the DTC fail this ignition cycle? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
  3. Turn ignition off. Disconnect the harness connector of the MAF sensor. Start engine. Observe the MAF sensor frequency parameter with a scan tool. Does the scan tool display zero Hz? If yes, go to step  5. If no, go to next step.
  4. Inspect the harness of the MAF sensor for incorrect routing that is too close to the following components:
    • The secondary ignition wires or the coils.
    • Any solenoids.
    • Any relays.
    • Any motors.

    Did you find and correct the condition? If yes, go to step  9. If no, go to step  6.

  5. Test for an intermittent and for a poor connection at the MAF sensor. Did you find and correct the condition? If yes, go to step  9. If no, go to step  7.
  6. Test for an intermittent and for a poor connection at the PCM. Did you find and correct the condition? If yes, go to step  9. If no, go to step  8.
  7. Replace MAF sensor. See appropriate REMOVAL & INSTALLATION article. After repairs, go to step  9.
  8. Replace PCM. See appropriate REMOVAL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  9. Clear the DTCs with a scan tool. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running DTC. See CONDITIONS FOR RUNNING DTC . Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  10. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.