U2090 Lost Communication with the Fuel Pump Control Module
The OBD2 code U2090 indicates a loss of communication between the vehicle's main control module and the fuel pump control module, which may affect fuel delivery and engine performance
Definition
Common causes
- Faulty Fuel Pump Control Module
- Damaged wiring or connectors
- Poor ground connection
- Blown fuse
- Faulty Engine Control Module (ECM)
- Corroded terminals
- Intermittent electrical issues
- Software issues or updates needed
- Fuel pump failure
- Communication network issues (CAN bus problems)
Common misdiagnoses
- Faulty fuel pump
- Bad fuel pump relay
- Wiring issues or shorts
- Defective engine control module (ECM)
- Faulty fuel level sensor
- Corroded connectors
- Issues with the powertrain control module (PCM)
- Battery or charging system problems
- Faulty ignition switch
- Software issues or updates needed in the ECM/PCM
Troubleshooting steps
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1. Check for Additional Codes
Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues
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2. Inspect the Wiring and Connectors
Visual Inspection: Check the wiring harness and connectors related to the fuel pump control module for any signs of damage, corrosion, or loose connections
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3. Connector Pins
Ensure that the pins in the connectors are not bent, corroded, or pushed back
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4. Test the Fuel Pump Control Module
Power and Ground: Verify that the fuel pump control module is receiving the correct power and ground signals. Use a multimeter to check voltage and ground continuity
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5. Module Functionality
If possible, test the fuel pump control module separately to ensure it is functioning correctly
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6. Check for Communication Issues
CAN Bus Communication: Since U2090 is a communication-related code, check the CAN bus wiring for shorts, opens, or other issues. Use a scan tool to monitor communication between modules
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7. Other Modules
Ensure that other modules in the vehicle are functioning properly, as a fault in another module can affect communication
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8. Inspect the Fuel Pump
Fuel Pump Operation: Ensure that the fuel pump is operational. You can do this by listening for the pump's operation when the ignition is turned on or by testing the pump directly
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9. Fuel Pump Relay
Check the fuel pump relay for proper operation. A faulty relay can prevent the fuel pump from receiving power
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10. Check for Ground Issues
Ensure that all ground connections related to the fuel pump control module and fuel pump are secure and free of corrosion
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11. Perform a Reset
After addressing any issues found, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns
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12. Consult Technical Service Bulletins (TSBs)
Check for any manufacturer-specific TSBs related to the U2090 code or fuel pump control module issues. There may be known fixes or recalls
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13. Professional Diagnosis
If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have access to specialized diagnostic tools and knowledge of specific vehicle issues.Conclusion Troubleshooting the U2090 code involves a systematic approach to check for communication issues, inspect wiring and components, and ensure that the fuel pump and its control module are functioning correctly. Always refer to the vehicle's service manual for specific procedures and specifications