Code result
U0604
Lost Communication With Fuel Pressure Sensor B
High severity
What it means
The vehicle bus reports loss of communication with smart fuel pressure sensor B (typically common-rail or low-pressure side). The ECM loses its actual rail-pressure feedback for closed-loop control.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Bus wiring open or shorted
highOne of the most commonly reported causes for this code — check this first.
Module without power or ground
mediumA plausible cause — test and verify before replacing parts.
Module failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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