P0112

Description
IAT SENSOR CIRCUIT LOW VOLTAGE

Intake Air Temperature (IAT) sensor is a thermistor that
varies resistance based on temperature. As temperature of sensor
increases, resistance decreases. High temperature will result in a low
signal voltage. DTC will set when PCM sees an IAT sensor voltage of
less than 0.82 volt for 10 seconds after engine runs for 100 seconds.
Symptoms
SES Service Engine Soon light

Causes

• Defective IAT sensor
• Loose or corroded connection at IAT sensor
• Open in IAT ground circuit or signal circuit
• Short to voltage in IAT signal circuit or reference circuit
• IAT harness and/or wiring routed too close to high-voltage wiring such as alternator, spark plug cables, etc.

Possible Solutions

• Inspect connection at IAT, clean if needed
• Test wires for short or open circut
• Check routing of wires and move away from high voltage wires
• Replace IAT sensor