P0190Powertrain
Powertrain · SAE
Fuel Rail Pressure Sensor Circuit — Fault
Meaning
The electrical circuit of the common-rail pressure sensor is faulty. The ECU is not receiving a reliable reading of injection pressure.
Common causes
- Failed rail pressure sensor
- Open, shorted or corroded wiring/connector
- Faulty supply voltage or reference ground
- Out-of-range signal from an intermittent contact
- Interference on the signal wire
- Rarely, a faulty input inside the ECU
Symptoms
- Limp mode
- Hard starting
- Power loss
- Irregular running
- Check-engine light on
Severity
High: without a reliable pressure reading the vehicle often enters limp mode.
What to do
- Read live data and compare the reported rail pressure with plausible values
- Check the sensor's supply, ground and signal with a multimeter
- Inspect the connector and wiring for corrosion or intermittent contacts
- Replace the sensor if supply and wiring are correct but the signal stays abnormal