MASS AIR FLOW (MAF) SENSOR INSPECTION [ZY]

Note

• Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart. (See Troubleshooting Procedure.)

Visual inspection

1. Visually inspect the MAF sensor for the following:

• Damage, cracks

• Rusted sensor terminal

• Bent sensor terminal

- If there is any malfunction, replace the MAF/IAT sensor. (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION [ZY].)

Voltage Inspection

1. Remove the MAF/IAT sensor without disconnecting the MAF/IAT sensor connector.

2. Turn the ignition switch to the ON position.

3. As the air gradually approaches the MAF detection part of the MAF/IAT sensor, verify that the MAF sensor output voltage (WDS PID: MAF) varies.

• If it cannot be verified even though the related wiring harnesses have no malfunction, replace the MAF/IAT sensor. (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION [ZY].)

• If the monitor item condition/specification (reference) is not within the specification, even though there is no malfunction, perform the "Circuit Open/short inspection".

Circuit Open/Short Inspection

1. Remove the PCM connector cover.

2. Disconnect the PCM connector. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [ZY].)

3. Disconnect the MAF/IAT sensor connector.

4. Inspect the following wiring harness for open or short circuit (Continuity inspection).

Open circuit

• If there is no continuity, there is an open circuit. Repair or replace the wiring harness.

- MAF/IAT sensor terminal A and PCM terminal 2BC

- MAF/IAT sensor terminal B and PCM terminal 2U

- MAF/IAT sensor terminal C and PCM terminal 2V

Short circuit

• If there is continuity, there is a short circuit. Repair or replace the wiring harness.

- MAF/IAT sensor terminal A and power supply

- MAF/IAT sensor terminal A and body GND

- MAF/IAT sensor terminal B and power supply

- MAF/IAT sensor terminal C and power supply

- MAF/IAT sensor terminal C and body GND