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Home >> Chevy Truck >> 2013 >> Express 4500 V8-6.6L DSL Turbo >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P242C

P242C




DTC P0545, P0546, P2032, P2033, P242C, P242D, P2470, or P2471

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 P0545
- Exhaust Gas Temperature Sensor 1 Circuit Low Voltage

DTC P0546
- Exhaust Gas Temperature Sensor 1 Circuit High Voltage

DTC P2032
- Exhaust Gas Temperature Sensor 2 Circuit Low Voltage

DTC P2033
- Exhaust Gas Temperature Sensor 2 Circuit High Voltage

DTC P242C
- Exhaust Gas Temperature Sensor 3 Circuit Low Voltage

DTC P242D
- Exhaust Gas Temperature Sensor 3 Circuit High Voltage

DTC P2470
- Exhaust Gas Temperature Sensor 4 Circuit Low Voltage

DTC P2471
- Exhaust Gas Temperature Sensor 4 Circuit High Voltage

Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The exhaust gas temperature sensors are variable resistors that measure the temperature of the exhaust at the inlet and outlet of the diesel oxidation catalyst as well as the inlet and outlet of the diesel particulate filter (DPF). The engine control module (ECM) supplies a bias 5-volt signal to the exhaust gas temperature sensor signal circuit, and supplies a ground to the low reference circuit. The exhaust gas temperature information is used by the ECM during the particulate filter cleaning process.

The following table illustrates the relationship between the temperature of the exhaust gas and the resistance and voltage at the exhaust gas temperature sensor.






Conditions for Running the DTC

* The ignition is ON or the engine is running.

* The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P0545, P2032, P242C and P2470

The ECM detects that the exhaust gas temperature sensor voltage is less than 0.65 V for greater than 5 s.

P0546, P2033, P242D and P2471

The ECM detects that the exhaust gas temperature sensor voltage is greater than 2.21 V for greater than 5 s.

Action Taken When the DTC Sets

P0545, P0546, P2470 and P2471

DTCs P0545, P0546, P2470 and P2471 are Type B DTCs.

P2032

* DTC P2032 is a Type A DTC.

* Diesel particulate filter regeneration is inhibited

* Emission control warning strategy is activated. Refer to Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality)Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level)Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control) Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control)Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) for more information.

P2033

* DTC P2033 is a Type A DTC.

* Diesel particulate filter regeneration is inhibited

* Selective catalyst reductant dosing is inhibited

* Emission control warning strategy is activated. Refer to Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality)Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level)Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control) Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control)Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) for more information.

P242C and P242D

* DTCs P242C and P242D are Type A DTCs.

* Selective catalyst reductant dosing is inhibited.

* Emission control warning strategy is activated. Refer to Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality)Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level) Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Level)Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control) Diesel Exhaust Fluid (DEF) Warning Strategy (Emission Control)Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering) for more information.

Conditions for Clearing the DTC

* DTCs P0545, P0546, P2470 and P2471 are Type B DTCs.

* DTCs P2032, P2033, P242C and P242D are Type A DTCs.

Diagnostic Aids

* Inspect the exhaust gas temperature sensor terminals for corrosion.

* Exhaust gas temperature sensors may fail intermittently while operating under extreme temperatures. Review the Freeze Frame Failure Records to verify the failure criteria.

* A plot of scan tool EGT sensor snapshot data taken while the engine is running at extreme temperatures may increase the ability to diagnose an intermittent EGT sensor.

* A short to a separate 5 V source will cause this DTC to set.

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)

Description and Operation

Exhaust Aftertreatment System Description Exhaust Aftertreatment 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 for scan tool information

Special Tools

J 25070 - Heat Gun 500-750°F

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P113A, P20E2, P2080, P2084, P242B, or P246F is not set.

• If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle

• If none of the DTCs are set

3. Engine running at operating temperature.

4. Increase engine speed to 2,500 RPM for 5 minutes while observing the appropriate scan tool EGT Sensor 1-4 parameter. The temperature should increase smoothly within the normal range of -39 to +999°C (-38 to +1,830°F) with no spikes or dropouts.

• If spikes or dropouts occur
Refer to Circuit/System Testing.

• If no spikes or dropouts occur

5. 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.

6. Verify a DTC does not set.

• If any DTC sets
Refer to Circuit/System Testing.

• If a DTC does not set

7. All OK.

Circuit/System Testing

Note: Perform the Repair Verification after completing the Circuit/System Testing.

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate B131 EGT sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 ohms between the low reference circuit terminal B and ground.

• If 5 ohms or greater

1. Ignition OFF, disconnect the harness connector at the K20 engine control module.

2. Test for less than 2 ohms in the low reference circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K20 engine control module.

• If less than 5 ohms

3. Ignition ON.

4. Verify the scan tool B131 EGT sensor parameter is greater than 998°C (1828°F).

• If 998°C (1828°F) or less

1. Ignition OFF, disconnect the harness connector at the K20 engine control module.

2. Test for infinite resistance between the signal circuit terminal A and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance, replace the K20 engine control module.

• If greater than 998°C (1828°F)

5. Install a 3 A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B.

6. Verify the scan tool B131 EGT parameter is less than -35°C (-31°F).

• If -35°C (-31°F) or greater

1. Ignition OFF, disconnect the harness connector at the K20 engine control module, ignition ON.

2. Test for less than 1 V between the signal circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

3. Ignition OFF

4. Test for less than 2 ohms in the signal circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K20 engine control module.

• If less than -35°C (-31°F)

7. Test or replace the B131 Exhaust Gas Temperature sensor.

Component Testing

Note: The J 25070 Heat Gun 500-750°F may be used to evaluate the sensor under high temperature conditions.



1. Ignition OFF, remove the affected B131 EGT sensor while leaving the harness connector connected.

2. Measure and record the resistance of the B131 EGT sensor and compare the measurements to the Temperature Versus Resistance (Fuel Temperature Sensor) Temperature Versus Resistance (Fuel Temperature Sensor)Temperature Versus Resistance (ECT Sensors) Temperature Versus Resistance (ECT Sensors)Temperature Versus Resistance (IAT Sensor 1) Temperature Versus Resistance (IAT Sensor 1)Temperature Versus Resistance (IAT Sensor 2) Temperature Versus Resistance (IAT Sensor 2)Temperature Versus Resistance (EGT Sensors) Temperature Versus Resistance (EGT Sensors)Temperature Versus Resistance (EGR Temperature Sensors) Temperature Versus Resistance (EGR Temperature Sensors)Temperature Versus Resistance (Emission Reduction Fluid Injector) [1][2]Diesel Emissions Fluid (DEF) System chart.

• If not within the specified range
Replace the B131 EGT sensor.

• If within the specified range

3. All OK

Repair Instructions

* Exhaust Temperature Sensor Replacement - Position 1 Exhaust Temperature Sensor Replacement - Position 1

* Exhaust Temperature Sensor Replacement - Position 2 Exhaust Temperature Sensor Replacement - Position 2

* Exhaust Temperature Sensor Replacement - Position 3 Exhaust Temperature Sensor Replacement - Position 3

* Exhaust Temperature Sensor Replacement - Position 4 Exhaust Temperature Sensor Replacement - Position 4

* Perform the scan tool Diesel Particulate Filter (DPF) Regeneration Enable Diesel Particulate Filter (DPF) Regeneration Enable procedure if the scan tool DPF Soot Mass is less than 30 g. If the scan tool DPF Soot Mass is 30 g or greater, perform the Diesel Particulate Filter (DPF) Service Regeneration Diesel Particulate Filter (DPF) Service Regeneration procedure.

* 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, all vehicle systems OFF, including retained accessory power (RAP) and the scan tool. This may take up to 2 minutes.

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 the Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle

6. Ignition ON, perform the Reductant System Data Reset with a scan tool in order to clear the DEF lamp.

• If the DEF lamp does not turn OFF, a condition with the system still exists.

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