The mass air flow (MAF) sensor is an air flow meter that measures the amount of air entering the engine. The control module uses the MAF sensor signal to provide the correct fuel delivery for all engine speeds and loads. The MAF sensor is a hot wire design. A platinum hot wire and a thermistor are located in the intake air bypass passage of the MAF sensor housing. The temperature of the platinum hot wire is affected by exposure to air flow and by exposure to air temperature. The platinum hot wire is maintained at a set temperature by controlling the current flow through the wire. The MAF sensor converts the changes in current flow to a voltage signal. The voltage signal from the MAF sensor enables the PCM to detect changes in air density and changes in air volume.

P0100

The PCM detects an open or a short in the MAF sensor signal.

P0102

The MAF sensor signal is less than 0.2 volt, for greater than 3 seconds.

P0103

The MAF sensor signal is greater than 4.9 volts, for greater than 3 seconds.

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

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

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Engine running for 1 minute, verify the MAF sensor scan tool parameter is between 1.5-5.0 g/s.
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 10 ohms between the MAF sensor signal low circuit terminal 2 and ground G104.

⇒	If greater than the specified range, test the signal low circuit for an open/high resistance. If the circuit tests normal, replace the PCM.

3. Ignition ON, test for battery voltage on the ignition 1 voltage circuit terminal 1.

⇒	If less than B+, repair the open/high resistance in the ignition 1 voltage circuit.

4. Verify the scan tool MAF sensor parameter is less than 0.5 g/s.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the PCM.

5. Connect a test lamp between the ignition 1 voltage circuit terminal 1 and the signal circuit terminal 3. Verify the MAF sensor parameter is greater than 220 g/s.

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

6. If all circuits test normal, test or replace the MAF sensor.

1. Ignition OFF, disconnect the harness connector at the MAF sensor.

Important: This test is valid only when the MAF sensor circuits test normal.

2. Install 3 jumper wires between the MAF sensor and the harness connector terminal as listed:

•	MAF sensor signal low circuit terminal 2

•	MAF sensor signal high circuit terminal 3

•	MAF sensor ignition positive voltage circuit terminal 1

3. Ignition ON, measure for voltage on the MAF signal circuit when blowing air thru the MAF sensor.

⇒	If the signal voltage did not increase with air flow, replace the MAF sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.