P0114
DTC P0112, P0113, or P0114 (LUW)
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. 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 and P0113
* The ignition is ON, or the engine is running.
* The battery voltage is greater than 9 V.
P0114
* DTC P0112, or P0113 is not set.
* The ignition is ON, or the engine is running.
* The battery voltage is greater than 9 V.
Conditions for Setting the DTC
P0112
The ECM detects that the IAT sensor voltage is less than 0.15 V for greater than 0.1 s.
P0113
The ECM detects that the IAT sensor voltage is more than 4.85 V for greater than 0.1 s.
P0114
The ECM detects that the IAT sensor signal has abruptly changed a minimum of 10°C (18°F) warmer or colder for greater than 2 s.
Action Taken When the DTC Sets
DTCs P0112, P0113 and P0114 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0112, P0113 and P0114 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LUW) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left (D6I)
Description and Operation
Air Intake System Description Air Intake System Description
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 Control Module References
Circuit/System Verification
1. If the ignition has been OFF for 8 h or greater, the IAT, the ambient air temperature, and the engine coolant temperature (ECT) should be within 9°C (16°F) of each other. Ignition ON, observe the scan tool IAT Sensor, Ambient Air Temperature, and the ECT Sensor 1 parameters. Compare those sensor parameters to each other to determine if the condition is current.
2. Engine running, observe the scan tool IAT Sensor parameter. The reading should be between -40 to +140°C (-34 to +284°F) depending on the current ambient temperature and the vehicle operating conditions.
3. Operate the vehicle within the Conditions for Running the DTC. 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 for 90 s, test for less than 5 ohm between the low reference circuit terminal 1 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
3. Ignition ON, verify the scan tool IAT Sensor is at -40°C (-40°F).
• If warmer than the specified range, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
Caution: If the fuse in the jumper wire opens, the signal circuit may have a short to a voltage or a short to ground and the sensor might be damaged.
4. Install a 3 A fused jumper wire between the signal circuit terminal 3 and ground. Verify the scan tool IAT Sensor is at 140°C (284°F).
• If less 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 Engine Control Module.
5. If all circuits test normal, test or replace the B75B Mass Air Flow/Intake Air Temperature Sensor.
Component Testing
Static Test
Measure and record the resistance of the B75B Mass Air Flow/Intake Air Temperature Sensor at various ambient temperatures, then compare those measurements to the Temperature Versus Resistance (IAT) Temperature Versus Resistance (IAT) table.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Mass Airflow Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming and setup