DTC Troubleshooting: P0112 (10-1)

DTC P0112 (10-1):  IAT Sensor Circuit Low Voltage

1.Turn the ignition switch ON (II).

2.Check the IAT with the scan tool.

Is 150°C (302°F) or higher (or H-Limit in Honda mode of PGM Tester) or 0 V indicated?


YES - Go to 3.


NO - Go to 9.


3.Disconnect the IAT sensor 2P connector.

4.Check the IAT with the scan tool.

Is 150°C (302°F) or higher (or H-Limit in Honda mode of PGM Tester) or 0 V indicated?


YES - Go to 5.


NO - Replace the  IAT sensor.n


5.Turn the ignition switch OFF.

6.Disconnect the negative cable from the battery.

7.Disconnect ECM/PCM connector B (24P).

8.Check for continuity between IAT sensor 2P connector terminal No. 2 and body ground.

 

Is there continuity?


YES - Repair short in the wire between the  ECM/ PCM (B17) and the  IAT sensor.n


NO - Substitute a known-good ECM/PCM and recheck. If the symptom/indication goes away, replace the original  ECM/ PCM.n

9.Check the temperature reading on the scan tool.
Be aware that if the engine is warm, the reading will be higher than ambient temperature. If the engine is cold, the IAT and ECT will have the same value.

Is the correct ambient temperature indicated?


YES - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the  IAT sensor and at the  ECM/ PCM.n


NO - Replace the  IAT sensor.n