GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Opel 🢒 2008 🢒 Antara 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0101

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptor

DTC P0101: Mass Air Flow (MAF) Sensor Circuit Performance

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Ignition 1 Voltage

P0100

P0100

P0100

--

P0101

MAF Sensor Signal

P0100

P0102

P0100

P0102

P0101

Low Reference

--

P0102

P0100

--

P0101

Circuit/System Description

The mass air flow (MAF) sensor is located in the air intake duct. The MAF sensor is an airflow meter that measures the amount of air that enters the engine. The MAF sensor uses a hot film that is cooled by air flowing past the sensing film as air enters the engine. The amount of cooling is proportional to the amount of the air flow. As the air flow increases, greater current is required in order to maintain the hot film at a constant temperature. The engine control module (ECM) uses the MAF sensor in order to provide the correct fuel delivery for all operating conditions.

Conditions for Running the DTC
    • Before the ECM can report DTC P0101 failed, DTCs P0100, P0102, P0103, P0111, P0112, P0113, P0121, P0122, P0123, P0221, P0222, P0223, P0335, P0336, and P0338 must run and pass.
    • DTC P2176 is not set.
    • The engine is operating for greater than 1 second.
    • The MAF sensor signal is greater than 1.4 grams per second.
    • The ignition voltage is greater than 11 volts.
    • The engine coolant temperature (ECT) is greater than 10°C (50°F).
    • The ECM detects greater than 150 revolutions of the crankshaft.
    • DTC P0101 runs continuously once the above conditions are met.

Conditions for Setting the DTC
    • The ECM detects that the MAF sensor signal is less than 0.14 g/s or greater than 278 g/s.
    • The condition exists for 4 seconds or for a cumulative of 50 seconds.

Action Taken When the DTC Sets

DTC P0101 is a Type B DTC.

Conditions for Clearing the DTC

DTC P0101 is a Type B DTC.

Diagnostic Aids
    • Inspect the harness of the MAF sensor in order to verify that it is not routed too close to the following components:
       - The secondary ignition wires or coils
       - Any solenoids
       - Any relays
       - Any motors
    • Inspect the hydro-carbon (HC) filter in the air cleaner assembly for ruptures that would leak charcoal into the air intake, contaminating the sensing element.
    • Inspect for any contamination, water intrusion, or debris on the sensing elements of the MAF sensor. If debris is present, clean the sensor. If the sensor cannot be cleaned, replace the sensor.
    • A high resistance may cause a driveability concern before this DTC sets.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Air Intake System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Engine idling for 1 minute, observe the scan tool DTC information. DTC P0101 should not set.
  2. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing
  1. Inspect for the following conditions:
    2. • An engine vacuum leak
    • An air leak in the intake air duct between the mass air flow (MAF) sensor and the throttle body
    • A plugged or collapsed intake air duct
    • Objects that block the MAF sensor air inlet
    • An air filter element that is restricted
    • The hydro-carbon absorber in the air cleaner assembly for ruptures or deterioration.
    • A restricted throttle plate or for carbon build-up around the throttle plate
    • An unseated engine oil dip stick
    • A loose or missing engine oil fill cap
    • An over filled crankcase
    ⇒If you find any of the above conditions, repair as necessary.
  2. Ignition OFF, disconnect the harness connector at the MAF sensor.
  3. Test for less than 5 ohms between the ground circuit terminal C and the ECM housing.
    4. ⇒If greater than the specified range, repair the ground circuit for an open/high resistance.

    Notice: 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.

  4. Ignition ON, load test for B+ between the ignition voltage circuit terminal B and ground.
    5. ⇒If less than the specified range, repair the ignition voltage circuit for an open/high resistance.
  5. Test for less than 5.1 volts between the signal circuit terminal A and ground circuit terminal C.
    6. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  6. Test for greater than 4 mA between the signal circuit terminal A and the ground circuit terminal C.
    7. ⇒If less than the specified range, test the signal circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the ECM.
  7. If all circuits test normal, replace the MAF sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Mass Airflow Sensor Replacement
    •  Control Module References for engine control module replacement, setup, and programming