Overview
| CODE | REASON | EFFECT |
| Fault Code: 687 PID: P103 SPN: 103 FMI: 1/18 LAMP: Amber SRT: |
Low turbocharger speed detected by the ECM.
|
Possible reduced engine performance. |
Circuit Description
The turbocharger speed sensor is a variable reluctance speed sensor. It consists of a coil of wire and an iron core. The target on the turbocharger shaft is a ground flat in the center of the shaft. As the flat on the turbocharger shaft spins past the speed sensor, a signal is generated. The Engine Control Module (ECM) interprets this signal and converts it to a turbocharger speed reading.
Component Location
The turbocharger speed sensor is mounted in the center housing of the turbocharger.
Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is running.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the turbocharger speed was less than 600 rpm for more than 1 second when the engine speed was greater than 1200 rpm.
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.
- The ECM will estimate the turbocharger speed.
Conditions for Clearing the Fault Code
- To validate the repair, use the recommended Cummins® electronic service tool or equivalent to perform the “Air Handling Performance Test” found in ECM Diagnostic Test.
- The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
- 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.
- 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.
Shop Talk
Possible causes of this fault code include:
- Malfunctioning or damaged turbocharger speed sensor.
- Malfunctioning or damaged intake manifold pressure/temperature sensor.
- Malfunctioning or damaged engine wiring harness.
Troubleshooting Summary
- Check for primary fault codes
- Technical Service Bulletin is available
- Turbocharger speed sensor check
- Intake manifold pressure sensor has carbon buildup
- Intake manifold pressure sensor stuck in-range
- Turbocharger speed sensor resistance check
- Turbocharger speed sensor open circuit check
- Turbocharger speed sensor circuit pin to ground short
- Turbocharger speed sensor circuit pin to pin short
- ECM calibration revision history check
- Turbocharger speed sensor is malfunctioning
Solution: S00000112
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:
- Intake manifold: 122, 123
- Barometric pressure: 221, 222
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Solution: S00011103
Verification
Conditions
- Turn keyswitch OFF.
Specification
- Proceed to the Repair section if the Technical Service Bulletin is applicable.
Linked Solutions
- None
Repair
- Complete the action outlined in the Technical Service Bulletin.
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.
Solution: S00002831
Verification
Conditions
- Turn keyswitch OFF.
Action
- Remove the turbocharger speed sensor from the turbocharger housing.
- Visually inspect the turbocharger speed sensor tip for damage.
Specification
- If the turbocharger speed sensor tip is damaged, then a malfunctioning turbocharger speed sensor has been detected.
Linked Solutions
- None
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.
Solution: S00009924
Verification
Conditions
- Turn keyswitch OFF.
Action
- Remove the intake manifold pressure/temperature sensor.
- Visually inspect the intake manifold pressure/temperature sensor tip for soot or carbon buildup.
- Visually inspect the intake manifold pressure sensor for damage.
- Visually inspect the intake manifold pressure sensor o-rings for damage.
Specification
- If any carbon buildup is found, then proceed to the Repair section.
- If nicks or cuts in or on the o-ring are identified, then a damaged intake manifold pressure/temperature sensor o-ring has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Clean the intake manifold pressure/temperature sensor.
- Replace the intake manifold pressure/temperature sensor o-ring.
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.
Solution: S00009926
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Use the recommended Cummins® electronic service tool or equivalent.
- Monitor the intake manifold pressure sensor.
Specification
- A malfunctioning intake manifold air pressure sensor has been detected if the intake manifold air pressure is not reading within the following specification: 0 ± 6.8 Kpa [0 ± 1 psi], 0 ± 51 mm-Hg [0 ± 2 in- Hg]
Linked Solutions
- None
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.
Solution: S00002828
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the turbocharger speed sensor from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the turbocharger speed sensor SUPPLY pin and the turbocharger speed sensor RETURN pin at the sensor.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- Proceed to the Repair section if the resistance is not within the following specification: 600 – 1600 Ω
Linked Solutions
- None
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.
Solution: S00000653
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the turbocharger speed sensor 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 turbocharger speed sensor SIGNAL pin at the turbocharger speed sensor wiring harness connector and the turbocharger speed sensor SIGNAL pin at the engine wiring harness ECM connector.
- Measure the resistance between the turbocharger speed sensor RETURN pin at the turbocharger speed sensor wiring harness connector and the turbocharger speed sensor 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
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.
Solution: S00000673
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the turbocharger speed sensor 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 from the turbocharger speed SIGNAL pin at the engine wiring harness ECM connector to engine block 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
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.
Solution: S00000652
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the turbocharger speed sensor from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the turbocharger speed 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
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.
Solution: S00000443
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.
Solution: S00010940
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
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.