P0114
DTC P0112, P0113, or P0114 (LAF) (2.4L)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0112
- Intake Air Temperature (IAT) Sensor Circuit Low Voltage
DTC P0113
- Intake Air Temperature (IAT) Sensor Circuit High Voltage
DTC P0114
- Intake Air Temperature (IAT) Sensor Circuit Intermittent
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The intake air temperature (IAT) sensor is a variable resistor. It is integrated into the mass air flow (MAF) sensor. The IAT sensor has a signal circuit and a low reference circuit. The IAT sensor measures the temperature of the air entering the engine. The engine control module (ECM) supplies 5 V to the IAT signal circuit, and a ground for the IAT low reference circuit.
Conditions for Running the DTC
P0112
* The engine run time is at least 1 s.
* The DTC runs continuously when the above conditions are met.
P0113
* The engine run time is at least 1 s.
* The DTC runs continuously when the above conditions are met.
P0114
* The ignition is ON or the engine is running.
* This DTC runs continuously within the enabling conditions.
Conditions for Setting the DTC
P0112
The ECM detects that the IAT sensor signal is warmer than 149°C (300°F) for at least 7 s.
P0113
The ECM detects that the IAT sensor signal is colder than -60°C (-76°F) for at least 7 s.
P0114
The ECM detects that the IAT sensor signal is intermittent or has abruptly changed for at least 4 s.
Action Taken When the DTC Sets
* DTCs P0112, P0113, and P0114 are Type B DTCs.
* The ECM commands the cooling fans ON.
Conditions for Clearing the DTC
DTCs P0112, P0113, and P0114 are Type B DTCs.
Diagnostic Aids
* Depending on the ambient temperature, an IAT sensor signal circuit or low reference circuit that is shorted to the MAF sensor signal circuit can cause a DTC P0113 and/or P0114 to set. This condition causes a rapid fluctuation in the IAT Sensor parameter.
* An IAT sensor signal circuit that is shorted to the MAF sensor ignition circuit can cause a DTC P0113 and/or P0114 to set.
* A MAF sensor ground circuit that is open will cause a DTC P0113 and/or a DTC P0114 to set.
Reference Information
Schematic Reference
Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Engine running, observe the scan tool IAT Sensor parameter. The reading should be between -40 to +149°C (-40 to +300°F) depending on the current ambient temperature and the vehicle operating conditions.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B75B mass air flow /intake air temperature sensor.
2. Ignition OFF, all vehicle systems OFF, this may take up to 2 minutes, test for less than 5 ohm between the low reference circuit terminal D and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance, or for a short to voltage. If the circuit tests normal, replace the K20 ECM.
3. Ignition ON, verify the scan tool IAT parameter is colder than -39°C (-38°F).
• If warmer than the specified range, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the K20 ECM.
Note: If the fuse in the jumper wire opens, the signal circuit is shorted to voltage and the sensor may be damaged.
4. Install a 3 A fused jumper wire between the signal circuit terminal E and ground. Verify the scan tool IAT parameter is warmer than 149°C (300°F).
• If colder than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
5. If all circuits test normal, test or replace the B75B mass air flow /intake air temperature sensor.
Component Testing
Measure and record the resistance of the IAT sensor of the B75B mass air flow /intake air temperature sensor, at various ambient temperatures, then compare those measurements to the Temperature Versus Resistance (Temperature Versus Resistance) table.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Mass Airflow Sensor with Intake Air Temperature Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming