P0112
DTC P0112: IAT Sensor Circuit Low Voltage1. Turn the ignition switch ON (II).
2. Check the IAT with the scan tool.
Is 302 °F (150 °C) or higher (or H-Limit in Honda mode of PGM Tester) or 0 V indicated?
YES - Go to step 3.
NO - Go to step 10.
3. Disconnect the IAT sensor 2P connector.
4. Check the IAT with the scan tool.
Is 302 °F (150 °C) or higher (or H-Limit in Honda mode of PGM Tester) or 0 V indicated?
YES - Go to step 5.
NO - Replace the IAT sensor.
5. Turn the ignition switch OFF.
6. Disconnect ECM connector C (31P).
7. Check for continuity between the IAT sensor 2P connector terminal No.2 and body ground.
Is there continuity?
YES -
- Go to step 8. (CVT model)
- Repair short in the wire between the ECM (C25) and the IAT sensor. (M/T model)
NO - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
8. Disconnect the TCM 22P connector.
9. Check for continuity between the IAT sensor 2P connector terminal No.2 and body ground.
Is there continuity?
YES - Repair short in the wire between the ECM (C25) and IAT sensor.
NO - Substitute a known-good TCM and recheck. If the symptom/indication goes away, replace the original TCM.
10. Check the temperature reading on the scan tool.
Is the correct ambient temperature indicated? If the engine is warm, the reading will be higher than ambient temperature.
YES - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the IAT sensor and at the ECM.
NO - Replace the IAT sensor.