2008 - MX-5 - Engine

INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION [LF]

NOTE:

• Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart. (See HOW TO USE THIS MANUAL.)

Resistance Inspection

1. Remove the battery cover.

2. Disconnect the negative battery cable. (See BATTERY REMOVAL/INSTALLATION [LF].)

3. Disconnect the MAF/IAT sensor connector.

4. Verify that the resistance between MAF/IAT sensor terminals D and E is within the specification.

• If the monitor item status/specification (reference) is not within the specification, even though the IAT sensor 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 [LF].)

Standard

Ambient temperature (°C {°F})	Resistance (kilohm)
20 {68}	2.21—2.69
60 {140}	0.493—0.667

Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION [LF].)

2. 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/IAT sensor terminal D and PCM terminal 1AT

• MAF/IAT sensor terminal E and PCM terminal 1AR

Short circuit

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

• MAF/IAT sensor terminal E and power supply

• MAF/IAT sensor terminal D and power supply

• MAF/IAT sensor terminal D and body ground