U0625: Lost Communication With Fuel Rail Pressure Sensor Bank 1

What it means

A control module has stopped receiving expected network messages from the fuel rail pressure sensor on bank 1. The effects on fuel control depend on the vehicle's system design.

At a glance

• Usually lights the warning light of the system that lost communication
• Affects emissions; the car can fail an emissions test
• The engine or gearbox may go into limp mode

How it works

The fuel rail pressure sensor on bank 1 sends pressure information over the vehicle network for engine control. The receiving module checks for the sensor's expected messages; U0625 sets when those messages stop arriving. Fuel control and engine performance may be affected depending on the vehicle.

Common causes

Most likely first.

1. Bus wiring open or shorted
2. Module without power or ground
3. Module failed

Symptoms

• Warning light or message related to the affected system
• Engine performance may be affected

How to diagnose it

1. Record freeze-frame data and scan all modules for communication and powertrain codes to see when the bank 1 sensor messages disappeared and whether other network faults are present.
2. Use live data to check whether fuel rail pressure from bank 1 is available and plausible, and compare it with related pressure readings if the vehicle provides them.
3. Inspect the bank 1 sensor, its connector, and nearby bus wiring for damage, corrosion, loose pins, or contamination.
4. Check the sensor module's power and ground against the manufacturer's specification, since a supply or ground fault can stop it communicating.
5. Test the relevant network wiring for opens or shorts using the vehicle wiring diagram and manufacturer's procedure before considering module replacement.

Common fixes

• Repair damaged or corroded bank 1 sensor connector or bus wiring.
• Restore the sensor module's power or ground connection.
• Repair an open or short in the communication bus serving the sensor.
• Replace the failed sensor module only after wiring, power, and ground test correctly.

Can I keep driving?

If the engine runs normally and no fuel-system warning or severe symptoms are present, drive only as needed and avoid hard acceleration or heavy loads. Stop if the engine stalls, loses power, or runs roughly, since fuel control may be unreliable.