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, more 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.

P0100

The ECM detects that the MAF sensor signal is 0.0 Hz.

P0102

The ECM detects that the MAF sensor signal is less than 1135 Hz.

P0103

The ECM detects that the MAF sensor signal is greater than 15,152 Hz.

DTCs P0100, P0102, and P0103 are Type B DTCs.

DTCs P0100, P0102, and P0103 are Type B DTCs.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Air Intake System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 38522 Variable Signal Generator

1. Engine idling for 1 minute, observe the DTC information with a scan tool. DTCs P0100, P0102 and P0103 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 you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the harness connector at the MAF sensor.
2. Ignition OFF, test for less than 5 Ω between the ground circuit terminal C and the battery ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

Caution: 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.

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

⇒	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.

4. Test for 4.8-5.2 V between the signal circuit terminal A and the ground circuit terminal C.

⇒	If less than the specified range, test the signal circuit for an open/high resistance or a short to ground. If the circuit/connections test normal, replace the ECM.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.

5. Ignition OFF, connect the red lead of the J 38522 to the signal circuit terminal A at the MAF/IAT sensor harness connector. Connect the battery voltage supply to B+, and ground the black lead.
6. Set the J 38522 Signal switch to 5 V, the Frequency switch to 5K, and the Duty Cycle switch to Normal.
7. Ignition ON, observe the scan tool MAF Sensor frequency parameter. The parameter should be between 4,950-5,025 Hz.

⇒	If the parameter is not within the specified range, replace the ECM.

8. If all circuits/connections test normal, replace the MAF sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.