EGR Valve Position Circuit – Voltage Below Normal or Shorted to Low Source
Overview
| CODE | REASON | EFFECT |
| Fault Code: 2272 PID: P27 SPN: 27 FMI: 4/4 LAMP: Amber SRT: |
Low signal voltage has been detected at the EGR valve position sensor circuit.
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Possible reduced engine performance.
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EGR Valve Position Circuit
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Circuit Description
The exhaust gas recirculation (EGR) valve is controlled by a brushless motor located on top of the EGR valve. The EGR valve motor uses three different motor legs to move the valve through its range of motion. The ECM uses the EGR motor A, B, and C wires to command the EGR valve to the appropriate position in order to meet EGR flow targets.The EGR valve motor contains three position sensors that detect the location of the EGR valve. These sensors report the position of the valve back to the ECM over the EGR valve position A, B, and C wires.
The EGR valve motor contains three position sensors that detect the location of the EGR valve. These sensors report the position of the valve back to the ECM over the EGR valve position A, B, and C wires.
Component Location
The EGR valve position sensor is internal to the EGR valve assembly and can not be serviced separately.
Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the EGR valve position sensor signal voltage was less than a calibratible value.
Action Taken When the Fault Code is Active
- The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
Exhaust gas recirculation (EGR) valve operation will be disabled.
Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.
Conditions for Clearing the Fault Code
- To validate the repair, perform a key cycle, and leave the key in the ON position for 1 minute.
- The fault code status displayed by the recommended Cummins electronic service tool or equivalent will change to INACTIVE immediately after the diagnostic runs and passes.
- The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
- For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
- The “Reset All Faults” command in the recommended Cummins electronic service tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.
EGR valve position sensor wiring shorted to ground, open circuit, or shorted to power supply.
Loss of the EGR valve position sensor supply voltage or the ground circuit.
Troubleshooting Summary
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins electronic service tool or equivalent.
Action
- Use the recommended Cummins electronic service tool or equivalent to read the fault codes.
Specification
Before troubleshooting this fault code, troubleshoot any fault code that is active or has more than one inactive count within the last 25 engine operating hours from the following list:
- Sensor supply 1: 352, 386
- Sensor supply 2: 187, 227
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the EGR valve from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Turn keyswitch ON.
- Measure the voltage between the EGR valve SUPPLY pin and the EGR valve RETURN pin at the EGR valve connector of the engine wiring harness.
Specification
- Proceed to the Linked Solutions section if voltage is not within the following specification: 4.75 – 5.25 VDC
Linked Solutions
- EGR valve circuit check
Repair
- No additional action is required for this solution.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the EGR valve from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the EGR valve SUPPLY pin at the EGR valve engine wiring harness connector and the EGR valve SUPPLY pin at the engine wiring harness ECM connector.
- Measure the resistance between the EGR valve RETURN pin at the EGR valve engine wiring harness connector and the EGR valve RETURN pin at the engine wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is greater than the following specification: 10 Ω
Linked Solutions
- None
Repair
- Repair or replace the engine wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect all components on the wiring circuit being tested.
Action
This test is NOT for checking the J1939 data link (+) and (-) pins since it may cause damage to the J1939 smart devices or sensors.
This test is NOT for checking the OEM wiring harness since it may cause damage to OEM smart devices or sensors.
- Perform the Circuit Load Test for the circuit being tested.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- If the voltage drop is not within specification, then a malfunctioning wiring harness has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Repair or replace the engine wiring harness.
- Repair or replace the OEM wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the EGR valve position sensor from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the EGR valve position sensor SIGNAL A pin at the EGR valve wiring harness connector and the EGR valve position sensor SIGNAL A pin at the engine wiring harness ECM connector.
- Measure the resistance between the EGR valve position sensor SIGNAL B pin at the EGR valve wiring harness connector and the EGR valve position sensor SIGNAL B pin at the engine wiring harness ECM connector.
- Measure the resistance between the EGR valve position sensor SIGNAL C pin at the EGR valve wiring harness connector and the EGR valve position sensor SIGNAL C pin at the engine wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is greater than the following specification: 10 Ω
Linked Solutions
- None
Repair
- Repair or replace the engine wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the EGR valve motor from the engine wiring harness.
- Disconnect the engine wiring harness connector from the ECM.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the EGR valve position SIGNAL A pin at the engine wiring harness ECM connector and ground.
- Measure the resistance between the EGR valve position SIGNAL B pin at the engine wiring harness ECM connector and ground.
- Measure the resistance between the EGR valve position SIGNAL C pin at the engine wiring harness ECM connector and ground.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is less than the following specification: 100k Ω
Linked Solutions
- None
Repair
- Repair or replace the engine wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the EGR valve from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the EGR valve position SIGNAL A pin at the engine wiring harness ECM connector and all other pins in the ECM connector.
- Measure the resistance between the EGR valve position SIGNAL B pin at the engine wiring harness ECM connector and all other pins in the ECM connector.
- Measure the resistance between the EGR valve position SIGNAL C pin at the engine wiring harness ECM connector and all other pins in the ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is less than the following specification: 100k Ω
Linked Solutions
- None
Repair
- Repair or replace the engine wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
Action
- Verify all preceding solution verifications for this fault code have been performed.
Specification
- If the fault code is still active or inactive with more than one count within the last 25 engine hours and all the preceding solution verifications have been performed, then proceed to the Repair section.
Linked Solutions
- None
Repair
- Replace the EGR valve.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
If all steps have been completed and no root cause has been identified, then follow the technical escalation process.