FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.
Home >> Chevy Truck >> 2012 >> Express 3500 V8-6.6L DSL Turbo >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P0113

P0113




DTC P0112 or P0113

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 provide an overview of each diagnostic category.

DTC Descriptors

DTC P0112

-
Intake Air Temperature (IAT) Sensor 1 Circuit Low Voltage

DTC P0113

-
Intake Air Temperature (IAT) Sensor 1 Circuit High Voltage

Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The intake air temperature (IAT) sensor 1 is a variable resistor that measures the temperature of the air at the mass air flow (MAF) sensor. The IAT Sensor 1 is part of the mass air flow (MAF/IAT) sensor assembly. The engine control module (ECM) supplies 5 V to the IAT sensor 1 circuit, and a ground for the IAT sensor 1 low reference circuit. The ECM monitors the IAT sensor 1 signal for an excessively high or low voltage, or for a voltage that is not in correlation with the fuel rail temperature sensor start up signal.

Conditions for Running the DTC

P0112 or P0113

* The engine is runnning for longer than 10 s.

* The DTCs run continuously when the above condition is met.

Conditions for Setting the DTC

P0112

The IAT Sensor 1 parameter is warmer than 148°C (299°F) for greater than 3 s. This is equal to or less than 0.08 V on the IAT signal circuit as measured by the ECM.

P0113

The IAT Sensor 1 parameter is colder than -39°C (-38°F) for greater than 3 s. This is equal to greater than 4.9 V on the IAT signal circuit as measured by the ECM.

Action Taken When the DTC Sets

* DTCs P0112 and P0113 are Type A DTCs.

* The ECM commands reduced engine power.

* The driver information center (DIC) or indicator may display reduced engine power.

Conditions for Clearing the DTC

DTCs P0112 and P0113 are Type A DTCs.

Diagnostic Aids

* With the ignition ON and the engine OFF, if the engine is cold, a properly functioning IAT Sensor 1 will gradually increase the scan tool IAT Sensor 1 parameter. This is due to the heat that is generated by the MAF sensor heating elements.

* Depending on the ambient temperature, an IAT Sensor 1 signal circuit or low reference circuit that is shorted to the MAF sensor signal circuit can cause a DTC P0113 to set. This condition can cause a rapid fluctuation in the IAT Sensor 1 parameter.

* An IAT Sensor 1 low reference circuit that is open can cause the IAT Sensor 1 parameter response to be sluggish. This condition may not necessarily set a DTC.

* Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories Checking Aftermarket Accessories.

* The Fuel Rail Temperature Sensor is located at the return line from the fuel rail. The Fuel Rail Temperature Sensor is also know as the Fuel Temperature Sensor 2.

* If DTC P0103 is also set, check for a disconnected MAF/IAT sensor.

Reference Information

Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)

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 for scan tool information

Circuit/System Verification

Note:

* Perform Steps 1 and 2 of this verification procedure only if the ignition has been OFF for 8 hours or more.

* The vehicle sitting in direct sun light or having the block heater ON will skew the results.

1. Ignition ON, observe the following scan tool parameters. The readings should be within 15°C (27°F) of each other.

* IAT Sensor 1 Sensor

* Start-Up ECT Sensor

* Ambiant Air Temp. Sensor

2. Ignition ON, observe the following scan tool parameters. The readings should be within 20°C (36°F) of each other.

* IAT Sensor 1 sensor

* Fuel Rail Temperature sensor

3. Engine idling, observe the scan tool IAT Sensor 1 parameter. The reading should be between -38 to +148°C (-36 to +298°F) depending on the current ambient temperature and the vehicle operating conditions.

4. Operate the vehicle within the Conditions for Running the DTC to verify that 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 mass air flow B75B MAF/IAT sensor.

2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohms between the IAT Sensor 1 low reference circuit terminal A and ground.

• If greater than the specified range, test the IAT Sensor 1 low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.

3. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohms between the MAF sensor low reference circuit terminal E and ground.

• If greater than the specified range, test the MAF sensor low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.

4. Ignition ON, verify the scan tool IAT Sensor 1 parameter is colder than -39°C (-38°F).

• If warmer than the specified range, test the IAT Sensor 1 signal circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.

Note:
If a short to voltage is found on the IAT Sensor 1 signal circuit, the 3A fuse in the jumper wire will open.

5. Install a 3A fused jumper wire between the IAT Sensor 1 signal circuit terminal B and ground. Verify the scan tool IAT Sensor 1 parameter is warmer than 148°C (298°F).

• If colder than the specified range, test the IAT Sensor 1 circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM.

6. If all circuits test normal, test or replace the B75B MAF/IAT sensor.

Component Testing

* Ignition OFF, disconnect the harness connector at the B75B MAF/IAT sensor.

* Measure the resistance between the IAT Sensor 1 signal terminal B and the IAT Sensor 1 low reference circuit terminal A at the IAT Sensor 1. Compare the value to the Temperature Vs Resistance table. Verify the resistance is within 5 % of the specification. Refer to Temperature Versus Resistance (Fuel Temperature Sensor) Temperature Versus Resistance (Fuel Temperature Sensor)Temperature Versus Resistance (IAT Sensor 1) Temperature Versus Resistance (IAT Sensor 1)Temperature Versus Resistance (EGT Sensors) Temperature Versus Resistance (EGT Sensors)Temperature Versus Resistance (IAT Sensor 2) Temperature Versus Resistance (IAT Sensor 2)Temperature Versus Resistance (ECT Sensors) Temperature Versus Resistance (ECT Sensors)Temperature Versus Resistance (EGR Temperature Sensors) Temperature Versus Resistance (EGR Temperature Sensors).

Repair Instructions

* Mass Airflow Sensor with Intake Air Temperature Sensor Replacement Mass Airflow Sensor with Intake Air Temperature Sensor Replacement

* Control Module References Control Module References for ECM replacement, setup, and programming

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.

2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.

3. Clear the DTCs.

4. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down

5. Duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

6. Perform the Diesel Particulate Filter (DPF) Service Regeneration Diesel Particulate Filter (DPF) Service Regeneration.

pro multis Credits:Operation CHARM About Operation CHARM