Diagnosis & Repair
- Connect scan tool to DLC No. 3 connector. See Figure. Turn ignition on. Using scan tool, monitor IAT sensor temperature. If temperature displayed is same as outside temperature, check IAT sensor and ECM connections. Problem is intermittent.
- If temperature displayed is 284°F (140°C) or more, go to step 5). If temperature displayed is -40°F (-40°C), turn ignition off. Disconnect IAT sensor connector. Connect a jumper wire between IAT wiring harness connector terminals. Turn ignition on. Using scan tool, monitor IAT sensor temperature.
- If temperature displayed is 284°F (140°C) or more, replace IAT sensor and retest. If temperature displayed is less than 284°F (140°C), turn ignition off. Remove jumper wire. Access ECM behind passenger's side kick panel. On A/T models, connect a jumper wire between terminals No. 9 (Brown/Black wire) and No. 12 (Yellow/Green wire) at ECM E6 connector. See Figure or Figure. On M/T models, connect a jumper wire between terminals No. 9 (Brown/Black wire) and No. 7 (Yellow/Green wire) at ECM E6 connector.
- On all models, if temperature displayed on scan tool is 284°F (140°C) or more, check and repair wiring harness between IAT wiring harness connector and ECM. See appropriate wiring diagram in WIRING DIAGRAMS - 2.7L article. If temperature displayed on scan tool is less than 284°F (140°C) or more, replace ECM and retest.
- Turn ignition off. Disconnect IAT sensor connector. Turn ignition on. If temperature displayed on scan tool is -40°F (-40°C), replace IAT sensor and retest. If temperature displayed is not -40°F (-40°C), turn ignition off.
- Access ECM behind passenger's side kick panel. Disconnect ECM E6 connector. See Figure or Figure. Turn ignition on. If temperature displayed is -40°F (-40°C), locate and repair short circuit in wiring harness between IAT sensor and ECM. See appropriate wiring diagram in WIRING DIAGRAMS - 2.7L article. If temperature displayed by scan tool is not -40°F (-40°C), replace ECM and retest.