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Home >> Chevrolet >> 2011 >> Caprice >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 6.0L - DTC Diagnostics And Troubleshooting >> Diagnostic Information and Procedures >> DTC P0101 or P1101 >> Circuit/System Testing

Circuit/System Testing

  1. Verify the following conditions do not exist:
    • A dirty or deteriorating air filter element
    • A leaking, loose, or cracked PCV pipe or seal
    • A restricted or collapsed air intake duct
    • A misaligned, leaking, or damaged air intake duct
    • Any objects blocking the air inlet probe of the mass air flow/intake air temperature sensor
    • Any contamination or debris on the sensing elements in the probe of the mass air flow/intake air temperature sensor
    • A cracked, damaged, or leaking mass air flow/intake air temperature sensor housing
    • Any water intrusion in the induction system
    • Any snow or ice build-up at the air cleaner or mass air flow/intake air temperature sensor in cold climates
    • Any vacuum leak
    • A MAP sensor seal that is leaking, missing, or damaged
    • An Intake manifold resonator with a leaking seal, or a cracked or broken housing
    • Throttle body for dirt, debris, and coking. Refer to Throttle Body Cleaning .
    • A damaged throttle body blade or shaft
    • Missing, restricted, or leaking exhaust components. Refer to Symptoms - Engine Exhaust .
    • If you find any of the above conditions, repair as necessary.
  2. Ignition OFF, disconnect the harness connector at the B75B mass air flow/intake air temperature sensor.
  3. 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 C and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal B and ground.
    • If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance.
  5. Test for 4.8-5.2 V between the MAF sensor signal circuit terminal A and ground.
    • If less than the specified range, test the MAF sensor signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
    • If greater than the specified range, test the MAF sensor signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  6. Ignition OFF, connect the red lead of the J-38522  variable speed generator to the MAF sensor signal circuit terminal A at the harness connector. Connect the battery voltage supply to B+, and the black lead to ground.
  7. Set the J-38522  variable speed generator to the following specifications.
    • Signal switch to 5 V
    • Frequency switch to 5 KHz
    • Duty Cycle switch to Normal
  8. Engine idling, observe the scan tool MAF Sensor parameter. The reading should be between 4, 950-5, 050 Hz.
    • If not within the specified range, replace the K20 ECM.
  9. If all circuits test normal, test or replace the B75B mass air flow/intake air temperature sensor.
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