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Air Temperature Sensor ( Ambient / Intake ): Testing and Inspection

IAT Sensor Resistance Inspection

1. Disconnect the MAF/IAT sensor connector.
2. Measure the resistance between MAF/IAT sensor terminals A and F using an ohmmeter.







- If not as specified, replace the MAF/IAT sensor.
- If the IAT sensor is okay, but the IAT PID is out of specification, perform the "IAT Sensor Circuit Open/Short Inspection".

IAT Sensor Circuit Open/Short Inspection

1. Disconnect the PCM connector.




2. Connect the SST (104 Pin Breakout Box) without connecting to the PCM as shown.
3. Tighten the connector attaching bolt.

Tightening torque 3.0-5.4 N.m {30-56 kgf.cm, 27-48 in.lbf}

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

Open circuit
- If there is no continuity, the circuit is open. Repair or replace the harness.




- MAF/IAT sensor terminal A (harness-side) and 104 pin breakout box terminal 20
- MAF/IAT sensor terminal F (harness-side) and 104 pin breakout box terminal 15.

Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the harness.
- MAF/IAT sensor terminal A (harness-side) and power supply
- MAF/IAT sensor terminal F (harness-side) and power supply
- MAF/IAT sensor terminal F (harness-side) and body ground