P041C
DTC P041C or P041D
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 P041C
- Exhaust Gas Recirculation (EGR) Temperature Sensor 1 Circuit Low Voltage
DTC P041D
- Exhaust Gas Recirculation (EGR) Temperature Sensor 1 Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The exhaust gas recirculation (EGR) temperature sensors are variable resistors that measure the temperature of the exhaust gas at the inlet and outlet of the EGR cooler. The engine control module (ECM) supplies 5 volts to the EGR temperature sensor signal circuit and a ground for the low reference circuit. When the EGR temperature sensor is cold, the sensor resistance is high. When the EGR temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a higher voltage on the EGR temperature signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the EGR temperature signal circuit.
Conditions for Running the DTC
* The engine speed is greater than 600 RPM for 10 s.
* The DTCs run continuously when the above conditions are met.
Conditions for Setting the DTC
P041C
The ECM detects that the EGR temperature Sensor 1 is less than 0.46 V for 5 s.
P041D
The ECM detects that the EGR temperature Sensor 1 is greater than 4.8 V for 5 s.
Action Taken When the DTC Sets
DTCs P041C and P041D are Type B DTCs.
Conditions for Clearing the DTC
DTCs P041C and P041D are Type B DTCs.
Diagnostic Aids
* Inspect the EGR temperature sensor terminals for corrosion.
* If the EGR temperature Sensor 1 signal circuit is shorted to a separate 5-volt source, the DTC will set.
* If the engine has cooled for at least 8 hrs, the scan tool EGR temperature sensor and the Engine Coolant temperature (ECT) sensor values should display within 3°C (5°F).
* EGR temperature sensors may fail while operating under extreme temperatures. Review the Freeze Frame/Failure Records to verify the failure criteria.
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
Special Tools
J 25070 Heat Gun 500-750°F
Circuit/System Verification
1. Engine running, observe the scan tool EGR cooler temperature Sensor 1 parameter. The reading should be within the normal range -39°C-999°C (-38°F-1830°F), and vary depending on 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 B130A EGR temperature Sensor 1.
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 ohm between the low reference circuit terminal 2 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 ECM.
3. Ignition ON, verify the scan tool EGR cooler temperature Sensor 1 parameter is -39°C (-38°F) or less.
• If greater than the specified range, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K20 ECM.
Note: If a short to voltage is found on the EGR temperature sensor signal circuit, the 3 A fuse in the jumper wire will open.
4. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool EGR cooler temperature Sensor 1 parameter is 999°C (1830°F) or greater.
• 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 ECM.
5. If all circuits test normal, test or replace the B130A EGR temperature Sensor 1.
Component Testing
Note: The J 25070 may be used to evaluate the sensor under high temperature conditions.
Measure and record the resistance of the B130A EGR temperature Sensor 1 and compare those measurements to the Temperature Versus Resistance Temperature Versus Resistance.
If the resistance is not within the specified range for the known temperature, replace the B130A EGR temperature Sensor 1.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Exhaust Gas Recirculation Valve Temperature Sensor Replacement - Position 1 (Exhaust Gas Recirculation Valve Temperature Sensor Replacement - Position 1)
* Control Module References (Programming and Relearning)for ECM replacement, setup, and programming