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Home >> Mazda >> 2000 >> MX-5 Miata L4-1.8L DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Air Temperature Sensor ( Ambient / Intake ) >> Testing and Inspection
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Air Temperature Sensor ( Ambient / Intake ): Testing and Inspection

Inspection of Resistance

NOTE: Perform the following test only when directed.

1. Disconnect the IAT sensor connector.
2. Remove the IAT sensor.
3. Place the IAT sensor in water with a thermometer, and heat the water gradually.




4. Measure the resistance of the IAT sensor using an ohmmeter.
- If IAT sensor is okay, but PID value is out of specification, perform the "Circuit Open/Short Inspection".
- If not as specified, replace the IAT sensor.

5. Reconnect the IAT sensor connector.

Circuit Open/Short Inspection

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




- Reference voltage circuit (IAT sensor connector terminal B and PCM connector terminal 2B.)
- Ground circuit (IAT sensor connector terminal A and PCM connector terminal 3F.)

Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the harness.
- IAT sensor connector terminal B and PCM connector terminal 2B to ground.
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