Air Flow Meter/Sensor: Testing and Inspection

MASS AIR FLOW (MAF) SENSOR INSPECTION [MZI-3.5]

NOTE: Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

Visual Inspection
1. Verify the following items of the MAF sensor.
- Damage, cracks
- Rusted sensor terminal
- Bent sensor terminal
- If there is any malfunction, replace the MAF sensor.

Voltage Inspection
1. Remove the MAF sensor with the connector still connected.
2. Turn the ignition switch to the ON position.
3. Verify that the MAF sensor output voltage (M-MDS monitor item: MAF) changes when wind is introduced gradually to the sensor part of the MAF sensor.
- If it cannot be verified even though the related harnesses have no malfunction, replace the MAF sensor.
- If the monitor item status/specification (reference) is not within the specification, even though the resistance is within the specification, perform the "Circuit Open/Short Inspection".

Circuit Open/Short Inspection

Circuit Open/Short Inspection:

1 Disconnect the PCM connector.
2. Disconnect the MAF/IAT sensor connector.
3. Inspect the following wiring harnesses for open or short. (Continuity inspection)

Open circuit
- If there is no continuity, the circuit is open. Repair or replace the wiring harness.
- MAF/IAT sensor terminal A and main relay No.1 terminal D
- MAF/IAT sensor terminal C and PCM terminal 1 AJ
- MAF/IAT sensor terminal D and PCM terminal 1 AN
- MAF/IAT sensor terminal E and PCM terminal 1 AL

Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the wiring harness.
- MAF/IAT sensor terminal A and body ground
- MAF/IAT sensor terminal C and power supply
- MAF/IAT sensor terminal C and body ground
- MAF/IAT sensor terminal D and power supply
- MAF/IAT sensor terminal D and body ground
- MAF/IAT sensor terminal E and power supply