Air Flow Meter/Sensor: Testing and Inspection

MASS AIR FLOW (MAF) SENSOR INSPECTION [LF, L3]

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

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 sensor.
- If the monitor item status/specification (reference) is not within the specification even though there is no malfunction, perform the "Circuit Open/Short Inspection".

Voltage Inspection

1. Remove the MAF/IAT sensor without disconnect 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 voltage at PCM terminal 1AK*1, 1AC*2 (M-MDS PID: MAF) varies.

- If it cannot be verified even though the related harnesses have no malfunction, replace the MAF/IAT sensor. Service and Repair

*1
California emission regulation applicable model and except for California emission regulation applicable model with LF MTX, L3
*2
Except for California emission regulation applicable model with LF ATX

Circuit Open/Short Inspection













1. Disconnect the PCM connector. Service and Repair

2. Disconnect the MAF sensor connector.

3. Inspect the following wiring harnesses for an 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 sensor terminal A and main relay terminal A
- MAF sensor terminal B and PCM terminal 1AR*1, 1AE*2
- MAF sensor terminal C and PCM terminal 1AK*1, 1AC*2

Short circuit

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

- MAF sensor terminal A and body ground
- MAF sensor terminal B and power supply
- MAF sensor terminal C and power supply
- MAF sensor terminal C and body ground

*1
California emission regulation applicable model and except for California emission regulation applicable model with LF MTX, L3
*2
Except for California emission regulation applicable model with LF ATX