U0603
Lost Communication With Fuel Pressure Sensor A
The vehicle bus reports loss of communication with smart fuel pressure sensor A (typically common-rail or low-pressure side). The ECM loses its actual rail-pressure feedback for closed-loop control.
The vehicle bus reports loss of communication with smart fuel pressure sensor A (typically common-rail or low-pressure side). The ECM loses its actual rail-pressure feedback for closed-loop control.
Common causes
- high
Bus wiring open or shorted
One of the most commonly reported causes for this code — check this first.
Typical part cost: $170-1100
- medium
Module without power or ground
A plausible cause — test and verify before replacing parts.
Typical part cost: $170-1100
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does U0603 mean?
U0603 means "Lost Communication With Fuel Pressure Sensor A". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U0603?
bus wiring open or shorted; module without power or ground; module failed — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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