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

INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION

NOTE: Perform the following inspection only when directed.

Resistance Inspection
1. Disconnect the negative battery cable.
2. Disconnect the MAF/IAT sensor connector.










3. Measure the resistance between the MAF/IAT sensor terminals D and E using an ohmmeter.
- If the IAT sensor is okay, but the PID value is out of specification, perform the "Circuit Open/Short Inspection".
- If not as specified, replace the MAF/IAT sensor. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)

Circuit Open/Short Inspection
1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION.)




2. Inspect the following harnesses for open or short circuit. (Continuity check).

Open circuit
- MAF/IAT sensor terminal D (harness-side) and PCM terminal 39 (harness-side)
- MAF/IAT sensor terminal E (harness-side) and PCM terminal 91 (harness-side)

Short circuit
- MAF/IAT sensor terminal D (harness-side) and power supply.
- MAF/IAT sensor terminal D (harness-side) and body GND.
- MAF/IAT sensor terminal E (harness-side) and power supply.