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Home >> Saab >> 2010 >> 9-5 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Management And Fuel System, V6 (2 Of 5) >> DTC P0101: Mass Air Flow (MAF) Sensor Performance >> Circuit/System Testing

Circuit/System Testing

  1. Verify the integrity of the entire air induction system by inspecting for the following conditions:
    • Any damaged components
    • Loose or improper installation
    • An air flow restriction
    • Any vacuum leak
    • Water intrusion
    • In cold climates, inspect for any snow or ice buildup
    • Inspect the B75 MAF sensor element for contamination.
  2. Ignition OFF, disconnect the harness connector at the B75 MAF sensor.
  3. Remove the fuse that supplies B+ to terminal 56 X2 of the ECM.
  4. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 Ω between the ground circuit terminal 2 and ground.
  5. If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Install fuse that supplies B+ to terminal 56 X2 of the ECM.
  7. WARNING: Do NOT use the low reference circuit in the component harness connector for this test. Damage to the control module may occur due to excessive current draw.

    Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 4 and ground.

  8. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all the components connected to the ignition circuit and replace as necessary.
  9. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 5 and ground.
  10. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
  11. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  12. Ignition OFF, connect the red lead of the J 38522 to the signal circuit terminal 5 at the B75 MAF sensor harness connector. Connect the battery voltage supply to B+, and the black lead to ground.
  13. Set the J 38522 Signal switch to 5 V, the Frequency switch to 5K, and the Duty Cycle switch to Normal.
  14. Engine idling, observe the scan tool MAF Sensor Hz parameter. The parameter should be between 4, 950-5, 050 Hz.
  15. If the MAF Sensor parameter is not within the specified range, replace the K20 ECM.
  16. If all circuits test normal, test or replace the B75 MAF sensor.
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