PGM-FI System

DTC Troubleshooting (cont'd)

11-61  

DTC P0112: 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 step 3.

NO

- Go to step 8.


  1. Disconnect the IAT sensor 2P connector.
  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 step 5.

NO

- Replace the IAT sensor.


  1. Turn the ignition switch OFF.
  2. Disconnect ECM/PCM connector B (24P).
  3. Check for continuity between the IAT sensor 2P connector terminal No. 2 and body ground.

IAT SENSOR 2P CONNECTOR

Wire side of female terminals

Is there continuity?

YES

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

NO

- Substitute a known-good ECM/PCM and recheck (see page 11-6). If symptom/indication goes away, replace the original ECM/PCM.


  1. 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.

NO

- Replace the IAT sensor.