DTC P0190 or P0191
Diagnostic Instructions
DTC Descriptors
DTC P0190 03: Fuel Rail Pressure Sensor Circuit Low Voltage
DTC P0190 07: Fuel Rail Pressure Sensor Circuit High Voltage
DTC P0191 11: Fuel Rail Pressure Sensor Performance High Input
DTC P0191 12: Fuel Rail Pressure Sensor Performance Low Input
Circuit/System Description
The fuel rail pressure sensor measures the fuel pressure within the fuel rail. The engine control module (ECM) monitors the voltage on the fuel rail pressure sensor circuits. When the fuel pressure is low, the signal voltage is low. When the fuel pressure is high, the signal voltage is high. The ECM supplies 5 V to the 5 V reference circuit and a ground to the low reference circuit. The fuel rail pressure sensor provides a signal voltage to the ECM, relative to the pressure changes within the fuel rail, on the fuel rail pressure sensor signal circuit.
Conditions for Running the DTC
• | The ignition is ON or the engine is running. |
• | The DTCs run continuously once the above condition is met. |
Conditions for Setting the DTC
P0190 03, P0190 07
The ECM detects that the fuel pressure sensor voltage is less than 0.46 V, or greater than 0.72 V for 2 s.
P0191 12
The ECM detects that the fuel pressure sensor voltage is less than 0.254 V for 0.5 s.
P0191 11
The ECM detects that the fuel pressure sensor voltage is greater than 4.7 V for 0.5 s.
Action Taken When the DTC Sets
• | DTCs P0190 03 and P0190 07 are Type A DTCs. |
• | DTCs P0191 11 and P0191 12 are Type B DTCs. |
Conditions for Clearing the DTC
• | DTCs P0190 03 and P0190 07 are Type A DTCs. |
• | DTCs P0191 11 and P0191 12 are Type B DTCs. |
Reference Information
Schematic Reference
Engine Controls Schematics : LLW
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition On, observe the DTC information with a scan tool. Verify that DTC P0651 is not set.
- Observe the scan tool Fuel Rail Pressure Sensor voltage parameter. The reading should be between 0.4-4.5 V.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the B47 Fuel Pressure Sensor.
- Test for less than 1 Ω between the low reference circuit terminal 1 and ground.
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground.
⇒ | If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
⇒ | If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module. |
- Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.8 V.
⇒ | If less than the specified range, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
- Install a 3 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.5 V.
⇒ | If greater than the specified range, test the signal circuit for short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- If all circuits test normal, test or replace the B47 Fuel Pressure Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
© Copyright Chevrolet. All rights reserved |