DTC P0112 - Intake Air Temp. (IAT) Sensor Circuit Low Input
- Turn ignition off. Disconnect IAT sensor harness connector. Turn ignition on. Using a voltmeter, measure voltage between ground and Light Blue wire of connector. If reading is 4 volts or greater, go to next step. If reading is not as specified, check Light Blue wire for short to Gray/Yellow wire or ground between IAT sensor harness connector and PCM. Repair as necessary. If wires are okay, replace PCM. Retest system.
- Disconnect negative battery cable. Remove IAT sensor from air cleaner. Using an ohmmeter, measure resistance between IAT sensor terminals while immersed in a container of water. Heat water slowly and ensure resistance changes as specified. See INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE table. If resistance is not as specified, replace IAT sensor. Retest system. If resistance is as specified, check for an intermittent problem. See TESTS W/O CODES article.
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE
| Temperature °F (°C) | Ohms |
|---|---|
| 32 (0) | 5880 |
| 68 (20) | 2210-2690 |
| 104 (40) | 1140 |
| 140 (60) | 580 |
| 176 (80) | 290-350 |