DTC P0112 Intake Air Temperature Sensor Circuit Low (4JJ3 with DPD)

1. DTC P0112 description

The IAT sensor is installed between the air cleaner and the turbocharger and is integrated with the MAF sensor. The IAT sensor is a variable resistor and measures the temperature of the air flowing into the engine. This sensor has a signal circuit and a low reference circuit. The ECM supplies 5 V to the signal circuit and ground to the low reference circuit. When the IAT sensor is cold, the resistance of the sensor is high. As the air temperature rises, the sensor resistance decreases. The ECM detects a high voltage when the sensor resistance is high. The ECM detects a low voltage when the sensor resistance is low. If the ECM detects an excessively low or high signal voltage, the DTC is set.

2. Condition for setting DTC P0112

Condition for running the DTC

The battery voltage is 9 to 16 V.
The ignition switch is ON.
DTCs P060B and P0697 are not set.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P060B Internal Control Module A/D Processing Performance".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P0697 Sensor Reference Voltage 3 Circuit".

Condition for setting the DTC

The ECM detects that the IAT sensor signal voltage is 0.1 V or less for 3 seconds.

3. Action taken when DTC P0112 sets

The ECM illuminates the MIL. Refer to Action taken when DTC sets - Type A.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".

The ECM limits the fuel injection quantity.
The ECM inhibits the EGR control.
The ECM inhibits the cruise control.
The ECM assumes a default IAT sensor value.

4. Condition for clearing DTC P0112

Refer to Conditions for clearing the MIL/DTC - Type A or Type B.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".