P0192
DTC P0191, P0192, or P0193
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0191
- Fuel Rail Pressure Sensor Performance
DTC P0192
- Fuel Rail Pressure Sensor Circuit Low Voltage
DTC P0193
- Fuel Rail Pressure Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The fuel rail fuel pressure sensor detects fuel pressure within the fuel rail. The engine control module (ECM) provides a 5 V reference voltage on the 5 V reference circuit and ground on the reference ground circuit. The ECM receives a varying signal voltage on the signal circuit. The ECM monitors the voltage on the fuel rail fuel pressure sensor circuits. When the fuel pressure is high, the signal voltage is high. When the fuel pressure is low, the signal voltage is low.
Conditions for Running the DTC
P0191
Condition 1
* The engine is not cranking.
* The ignition voltage is greater than 11 V.
* The vehicle speed is less than or equal to 1 km/h (0.62 mph).
* The low side fuel pressure is greater than or equal to 250 kPa (36 psi).
* The Accelerator Pedal Position is 0 percent for 2.5 s.
* The engine is running for greater than 30 s.
Condition 2 and 3
* The engine is not cranking.
* The ignition voltage is greater than 11 V.
* The engine speed is between 1,000-3,000 RPM.
* The vehicle speed is greater than or equal to 35 km/h (22 mph).
* The low side fuel pressure is greater than or equal to 250 kPa (36 psi).
* The Desired Fuel Rail Pressure is between 4-6 MPa (580-870 psi).
* The Accelerator Pedal Position is greater than or equal to 10 percent.
* The engine is running for greater than 30 s.
Condition 4
* DTC P0016, P0017, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0122, P0123, P0128, P0192, P0193, P0201, P0202, P0203, P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0340, P0341, P0351-P0354, P0365, P0366, P0506, P0507, P0628, P0697, P06A3, P0722, P0723, P1248, P1249, P124A, P124B, P1682, P2122, P2123, P2127, P2128, P2135, P2138, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157 is not set.
* The engine is not cranking.
* The vehicle speed is greater than or equal to 30 km/h (18.64 mph).
* The engine speed is greater than or equal to 2,000 RPM.
* The barometric (BARO) pressure is greater than 70 kPa.
* The intake air temperature (IAT) is warmer than -20°C (-4°F).
P0192 or P0193
* The engine is running.
* The ignition voltage is greater than 11 V.
* The DTCs run continuously within the enabling conditions.
Conditions for Setting the DTC
P0191
Condition 1
The difference between the low side fuel pressure and the high side fuel pressure is less than or equal to -1 MPa (-145 psi) or greater than or equal to 1 MPa (145 psi) with the high pressure fuel pump actuator commanded OFF. The condition exists for greater than 3 s.
Condition 2
The difference between the relief pressure and the measured high pressure is less than or equal to -1.6 MPa (-232 psi) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 2 s.
Condition 3
The difference between the commanded high pressure and the measured high pressure is greater than or equal to 3 MPa (435 psi) and the modeled injection pressure is greater than or equal to 1.6 MPa (232 psi) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 3 s.
Condition 4
The difference between the measured maximum high pressure and the measured minimum high pressure is less than or equal to 0.1 MPa (14.5 psi) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 30 s with the engine running or greater than 10 s with the engine cranking.
P0192
The ECM detects that the fuel rail fuel pressure sensor signal voltage is low for greater than 5 s.
P0193
The ECM detects that the fuel rail fuel pressure sensor signal voltage is high for greater than 5 s.
Action Taken When the DTC Sets
* DTCs P0191, P0192, and P0193 are Type A DTCs.
* A message center or an indicator may display Reduced Engine Power.
Conditions for Clearing the DTC
DTCs P0191, P0192 and P0193 are Type A DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left
Description and Operation
Fuel System Description Fuel System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify DTC P0641 is not set.
• If the DTC is set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.
• If the DTC is not set
3. Engine idling.
4. Verify DTC P0191, P0192 or P0193 is not set.
• If any of the DTCs are set
Refer to Circuit/System Testing.
• If none of the DTCs are set
5. 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.
6. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing.
• If the DTC does not set
7. All OK.
Circuit/System Testing
1. Ignition OFF and all vehicle systems OFF, disconnect the fuel injector multi-way harness connector X160. It may take up to 2 minutes for all vehicle systems to power down.
Note: Testing for steps 2 through 7 is performed on the ECM side of the multi-way harness connector.
2. Test for less than 5 ohms between the low reference circuit terminal 5 and ground.
• If 5 ohms or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If less than 5 ohms
3. Ignition ON.
4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 11 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the 5 V reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If between 4.8-5.2 V
5. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.
• If 0.02 V or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal 12 and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If less than 0.02 V
6. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the 5 V reference circuit terminal 11.
7. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.96 V.
• If 4.96 V or less
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 12 and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If greater than 4.96 V
8. Ignition OFF, remove the intake manifold.
9. Connect the fuel injector multi-way harness connector X160.
10. Disconnect the B47B fuel rail fuel pressure sensor connector.
Note: Testing for steps 11 through 17 is performed at the fuel rail fuel pressure sensor connector.
11. Test for less than 5 ohms between the low reference circuit terminal 3 and ground.
• If 5 ohms or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If less than 5 ohms
12. Ignition ON.
13. Test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the 5 V reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If between 4.8-5.2 V
14. Ignition ON.
15. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.
• If 0.02 V or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal 12 and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If less than 0.02 V
16. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the 5 V reference circuit terminal 1.
17. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.96 V.
• If 4.96 V or less
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If greater than 4.96 V
18. Replace the B47B fuel rail fuel pressure sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement
* Control Module References Control Module References for ECM replacement, setup, and programming