Exhaust Gas Pressure 1 – Data Valid But Above Normal Operating Range – Moderately Severe Level
Overview
| CODE | REASON | EFFECT |
| Fault Code: 2764 PID: P131 SPN: 1209 FMI: 0/16 LAMP: Amber SRT: |
High exhaust gas pressure has been detected by the exhaust gas pressure sensor.
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Possible reduced engine performance.
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Exhaust Gas Pressure Sensor Circuit
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Circuit Description
The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust manifold. This information is used by the engine control module (ECM) to control emissions and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The exhaust gas pressure sensor provides a signal to the ECM on the exhaust gas pressure sensor signal circuit. This sensor signal voltage changes, based on the pressure in the exhaust manifold.
Component Location
The exhaust gas pressure sensor is located above the front section of the exhaust manifold and is plumbed into the exhaust manifold.
Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is running.
Conditions for Setting the Fault Codes
Exhaust gas pressure sensor reading was greater than the engine protection limits.
Action Taken When the Fault Code is Active
An engine derate will be activated to bring exhaust gas pressure below the maximum operating limits.
Conditions for Clearing the Fault Code
- To validate the repair using a Diagnostic Road Test, utilize a route that incorporates both stop and go city type driving and steady state highway type driving. It may be necessary to load the unit for certain diagnostics in the ECM to run.
- To validate the repair using a Chassis Dynamometer, utilize a routine that incorporates acceleration and motoring events, steady state highway type operation, and load. This will simulate normal driving and allow the diagnostics in the ECM to run.
- 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.
- 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.
Possible causes of this fault code include:
A malfunctioning variable geometry turbocharger
A damaged in-range exhaust gas pressure sensor
A plugged or restricted aftertreatment diesel particulate filter
A plugged or restricted EGR cooler.
Troubleshooting Summary
- Check for primary fault codes
- Exhaust gas pressure sensor stuck in-range
- Plugged or damaged exhaust gas pressure sensor tube
- Plugged or damaged exhaust gas pressure sensor tube
- High exhaust restriction
- Aftertreatment DPF partially obstructed or plugged
- Exhaust gas pressure sensor circuit pin to pin short
- ECM calibration revision history check
- Stationary aftertreatment regeneration is needed
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:
- Exhaust gas pressure: 2373, 2374, 2554
- EGR differential pressure: 1866, 2273, 2274
- EGR: 1228, 1896, 1897, 1961, 2272, 2349, 2353, 3382, 3389, 4728
- Turbocharger: 595, 687, 1894, 1897, 1976, 2198, 2387, 2449, 2635, 2636, 6432
- Intake manifold: 122, 123, 124, 125, 2973, 3361, 4612, 5989, 5991
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins electronic service tool or equivalent.
Action
- Use the recommended Cummins electronic service tool or equivalent.
- Compare the exhaust gas pressure sensor reading to the barometric pressure.
Specification
- Proceed to the Linked Solution section if the exhaust gas pressure is not within the following specification of the barometric pressure: 76 mm Hg [3 in Hg]
Linked Solutions
- Plugged or damaged exhaust gas pressure sensor tube
Repair
- No additional action is required for this solution.
Validation
- None
Verification
Conditions
- Turn keyswitch OFF.
Action
- Remove the exhaust gas pressure sensor tube.
- Inspect the exhaust gas pressure sensor tube(s) for cracks and thread damage.
- Inspect the inside of the tube(s) and sensor adapter for debris or soot buildup.
Specification
- If plugging or damage is found, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Clean or replace the exhaust gas pressure sensor tube.
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
- Remove the exhaust gas pressure sensor tube.
- Inspect the exhaust gas pressure sensor tube(s) for cracks and thread damage.
- Inspect the inside of the tube(s) and sensor adapter for debris or soot buildup.
Specification
- If plugging or damage is found, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Clean or replace the exhaust gas pressure sensor tube.
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
- Install a mechanical gauge on the engine.
- Turn keyswitch ON.
- Start the engine.
- Check the exhaust restriction.
Specification
- If the exhaust restriction is not within specification, then a restriction in the exhaust has been detected.
Linked Solutions
- None
Repair
- Check the face of the aftertreatment diesel oxidation catalyst for plugging.
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 ON.
- Connect the recommended Cummins electronic service tool or equivalent.
Action
- If the aftertreatment DPF has already been replaced during this repair, then proceed to the next solution.
- Use the recommended Cummins electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Particulate Filter Automated Restriction Test.
Specification
- If the Aftertreatment Diesel Particulate Filter Automated Restriction Test exceeds the limits called out in procedure, then a plugged or restricted aftertreatment DPF has been detected.
Linked Solutions
- None
Repair
- Replace aftertreatment DPF.
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 exhaust gas pressure sensor from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the exhaust gas pressure sensor SIGNAL pin at the engine wiring harness ECM connector and all other pins in that 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
- Connect all components.
- 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.
- 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 revision listed in the ECM calibration revision history for applicable changes.
Specification
- If a calibration update for this fault code is available, the ECM calibration revision must be that revision or higher.
Linked Solutions
- None
Repair
- Prior to downloading the ECM calibration, check to see that all job images and all other troubleshooting has been documented as downloading an ECM calibration will remove the fault codes on the ECM.
- Download the updated ECM calibration code.
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 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.
- Check to make sure no other fault codes are active.
Specification
- If other fault codes that inhibit the aftertreatment stationary regeneration are active or inactive with more than one count within the last 25 engine operating hours, then troubleshoot those fault codes before performing the aftertreatment stationary regeneration procedure.
- If there are no other fault codes active or inactive with more than one count within the last 25 engine operating hours that inhibit the aftertreatment stationary regeneration, then proceed directly to performing the aftertreatment stationary regeneration.
Linked Solutions
- None
Repair
- Inform the customer on the proper procedure for initiating a stationary regeneration.
- Some vehicles can be equipped with a stationary regeneration switch in the dash. This switch can also be used to perform the stationary regeneration procedure. Refer to the manufacturer’s operating instructions.
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.