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Home >> Chevrolet >> 2012 >> Volt >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls/Fuel - 1.4L (LUU) - DTC P0010 To DTC P0499 >> Diagnostic Information and Procedures >> DTC P0101 >> Circuit/System Testing

Circuit/System Testing

  1. Verify the following conditions do not exist:
    • A dirty, restricted, 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 B75B Mass Air Flow/Intake Air Temperature sensor
    • Any contamination or debris on the sensing elements in the probe of the B75B Mass Air Flow/Intake Air Temperature sensor
    • A cracked, damaged, or leaking B75B 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 B75B Mass Air Flow/Intake Air Temperature sensor in cold climates
    • Any vacuum leak
    • A B74 Manifold Absolute Pressure sensor seal that is leaking, missing, or damaged
    • Q38 Throttle body for dirt, debris, and coking. Refer to Throttle Body Inspection and Cleaning .
    • A damaged Q38 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. Vehicle OFF, disconnect the harness connector at the B75B Mass Air Flow/Intake Air Temperature sensor.
  3. Vehicle in Service Mode, test for 4.8-5.2 V between the signal circuit terminal 5 and ground.
    • 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 Engine Control Module.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
  4. Verify that a test lamp illuminates between the ignition voltage circuit terminal 4 and ground.
    • If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition voltage circuit fuse is open, test or replace the components on the ignition voltage circuit.
  5. Connect the test lamp between the MAF control circuit terminal 2 and the ignition voltage circuit terminal 4.
  6. Vehicle in Service Mode, command the MAF Sensor Supply Voltage Low Side Driver ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
    • If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
  7. Vehicle OFF, connect the red lead of the J-38522  generator to the signal circuit terminal 5 at the harness connector. Connect the battery voltage supply to B+, and the black lead to ground.
  8. Set the J-38522  generator to the following specifications.
    • Signal switch to 5 V
    • Frequency switch to 5 KHz
    • Duty Cycle switch to Normal
    9. NOTE:

    The engine may run rough and stall.

  9. Vehicle ON, engine running, observe the scan tool MAF Sensor Hz parameter. The parameter should be between 4, 950 and 5, 025 Hz.
    • If not within the specified range, replace the K20 Engine Control Module.
  10. If all circuits test normal, test or replace the B75B Mass Air Flow/Intake Air Temperature sensor.
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