- Check Ground Circuit Turn ignition off. Disconnect IAT sensor harness connector. See «REMOVE/INSTALL/OVERHAUL»(ref-17990) article for IAT sensor location. Using an ohmmeter, check continuity between IAT sensor harness connector terminal No. 2 (Black wire) and engine ground. If no continuity exists, repair open in Black wire. If continuity exists, go to next step.
- Check Power Supply Turn ignition on. Using a voltmeter, measure voltage between IAT sensor harness connector terminal No. 1 (Sky Blue wire) and ground. If voltage is not approximately 5 volts, repair fault in Sky Blue wire as required. If voltage is approximately 5 volts, go to next step.
- Check Component Leave sensor disconnected. Measure resistance across sensor connector terminals. See INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE table. If resistance is not as specified, replace sensor. If resistance is as specified, check ECM connector for damage or corrosion. Disconnect and reconnect harness connectors in circuit and perform «FINAL CHECK»(ref-17943-S12355810372001121700000) , see appropriate section in this article.
| Temperature °F (°C) | Ohms |
|---|---|
| 68 (20) | 2100-2900 |
| 176 (80) | 300-330 |
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE