INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION


BHE014018840W03

Note
• Before performing the following inspection, make sure to follow the troubleshooting flowchart. (See Troubleshooting Procedure.)

Resistance Inspection

1. Disconnect the MAF/IAT sensor connector.

2. Verify that the resistance between MAF sensor terminals D and E is as indicated in the table while blowing hot air gradually into the IAT sensor part built into the MAF sensor.

• If the monitor item condition/specification (reference) is not within the specification, even though the resistance is within the specification, perform the "Circuit Open/Short Inspection".
• If not within the specification, replace the MAF/IAT sensor. (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION.)
IAT sensor resistance

Air temperature (°C {°F})

Resistance (kilohm)

-20 {-4}
13.6-18.4
20 {68}
2.21-2.69
60 {140}
0.493-0.667

IAT sensor characteristics graph (reference)

Circuit Open/Short Inspection

1. Disconnect the PCM connectors.

2. Disconnect the MAF/IAT sensor connector.

3. Inspect the following wiring harnesses for open or short circuit. (Continuity inspection)

Open circuit

• If there is no continuity in the following wiring harnesses, there is an open circuit. Repair or replace the wiring harness.
– MAF/IAT sensor terminal D and PCM terminal 5K
– MAF/IAT sensor terminal E and PCM terminal 4U

Short circuit

• If there is continuity in the following wiring harnesses, there is a short circuit. Repair or replace the wiring harness.
– MAF/IAT sensor terminal D and body ground
– MAF/IAT sensor terminal D and power supply