Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P0192: Fuel Rail Pressure (FRP) Sensor Circuit Low VoltageDTC P0193: Fuel Rail Pressure (FRP) Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
FRP Signal | P0192 | P0088, P0191 | P0193 | P0193 | -- |
FRP Low Reference | -- | P0191 | P0193 | ¹ | -- |
FRP 5-Volt Reference | P0117, P0462, P0522, P0652 | P0087, P0191 | P0193 | P0118, P0653 | -- |
Fuel Pressure Regulator Solenoid Supply Voltage | P0088, P0090 | P0088 | P0090 | P0087, P0191, P2510 | -- |
¹ Opens circuit fuse or opens circuit. | |||||
Typical Scan Tool Data
Circuit | Short to Ground | High Resistance | Open | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: The Ignition ON, with the Engine OFF Parameter Normal Range: 0.352-0.650 volt | ||||
5-Volt Reference | 0 MPa (0 psi) | Varies¹ | 200 MPa (29,000 psi) | 0 MPa (0.0 psi) |
FRP Sensor Signal | 0 MPa (0 psi) | Varies¹ | 200 MPa (29,000 psi) | 200 MPa (29,000 psi) |
FRP Sensor Low Reference | -- | Varies¹ | 200 MPa (29,000 psi) | Note² |
Fuel Pressure Regulator Solenoid Supply Voltage | 0.2 MPa (34.8 psi)¹ | 71 MPa (10,300 psi)¹ | 0.2 MPa (34.8 psi)¹ | 0.2 MPa (34.8 psi)¹ |
¹ Fuel pressure erratic ² Opens circuit fuse or opens circuit | ||||
Circuit/System Description
The fuel rail pressure (FRP) sensor has a 5-volt reference circuit, a signal circuit, and a low reference circuit. The engine control module (ECM) monitors the voltage on the FRP sensor circuits. When the fuel pressure is high, the signal voltage is high. When the fuel pressure is low, the signal voltage is low. The fuel pressure regulator has a solenoid supply voltage circuit and a solenoid control circuit. The ECM controls the fuel pressure regulator , which regulates high pressure fuel that goes to the fuel injector rails and the injectors.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | DTCs P0652 or P0653 are not set. |
| • | These diagnostics run continuously within the enabling conditions. |
Conditions for Setting the DTC
P0192
The ECM detects the signal circuit voltage that is less than 0.254 volts for more than one second.
P0193
The ECM detects that the signal circuit voltage is more than 4.75 volts for more than one second.
Action Taken When the DTC Sets
| • | DTCs P0192 and P0193 are Type A DTCs. |
| • | The ECM commands the engine to operate in the Reduced Engine Power mode. |
| • | The message center displays Reduced Engine Power. |
Conditions for Clearing the MIL/DTC
DTCs P0192 and P0193 are Type A DTCs.
Reference Information
Schematic Reference
Connector End View Reference
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
Important:
• You must perform the Circuit/System Verification before proceeding with Circuit/System Testing. • If you cannot duplicate the condition, operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
- Verify that DTCs P0652 or P0653 are not set.
- Observe the Fuel Rail Pressure Sensor parameter with a scan tool. During engine cranking, the pressure should be at least 10 MPa. With the engine running at idle, the pressure should be close to the Desired Fuel Rail Pressure. As the engine speed increases, the Desired Fuel Rail Pressure and the Fuel Rail Pressure Sensor should closely match each other.
- Engine running, observe the DTC information with a scan tool. DTCs P0192 or P0193 should not set.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame Records data.
| ⇒ | If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
Circuit/System Testing
Important: Fuel pressure control will be disable if DTC P0087, P0088, P0192, or P0193 are set. Codes must be cleared to enable the device control.
- Ignition OFF, disconnect the FRP sensor connector.
- Turn ON the ignition, with the engine OFF.
- Observe the Fuel Rail Pressure Sensor parameter with a scan tool The fuel pressure should be 200 MPa (29,000 psi).
- Probe the signal circuit with a test lamp connected to ground. The test lamp should not illuminate.
- Connect a fused jumper between the FRP signal circuit and the low reference circuit and observe the Fuel Rail Pressure Sensor parameter with a scan tool. The fuel pressure should be 0 MPa (0 psi).
- Connect a DMM between the FRP 5-volt reference circuit and ground, and measure the voltage. The voltage should be 4.8-5.2 volts.
- If all circuits test normal, replace the ECM.
| ⇒ | If the fuel pressure is 0 MPa (0 psi), test the FRP sensor signal circuit for a sort to ground. If the circuit tests normal, replace the FRP sensor. |
| ⇒ | If the test lamp illuminates, test the signal circuit for a short to voltage. |
| ⇒ | If the fuel pressure does not go to 0 MPa (0 psi), test the FRP sensor signal circuit and the low reference circuit for an open. If the circuit tests normal, replace the FRP sensor. |
| ⇒ | If the voltage is not within the specified range, test for an open in the 5-volt reference circuit. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, programing and setup |
