Diagnostic Aids

Malfunction code will set if at least 60 seconds have passed since engine was started, engine is idling and Intake Air Temperature (IAT) sensor temperature input to Engine Control Module (ECM) is less than -36°F (-38°C) or IAT sensor input to Engine Control Module (ECM) is more than 262°F (128°C). Check for following possible problems:

• Open or short between IAT sensor and Main relay.
• Open or short between IAT sensor and ECM.
• Short between IAT sensor wires.
• Faulty IAT sensor.