DTC P0090-P0092, P00C8, P00C9, or P00CA
Diagnostic Instructions
DTC Descriptors
DTC P0090: Fuel Pressure Regulator Control Circuit
DTC P0091: Fuel Pressure Regulator Control Circuit Low Voltage
DTC P0092: Fuel Pressure Regulator Control Circuit High Voltage
DTC P00C8: Fuel Pressure Regulator High Control Circuit
DTC P00C9: Fuel Pressure Regulator High Control Circuit Low Voltage
DTC P00CA: Fuel Pressure Regulator High Control Circuit High Voltage
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
High Pressure Fuel Pump Actuator High Control
| P0091, P00C9
| P0090, P00C8
| P0092, P00CA
| -
|
High Pressure Fuel Pump Actuator Low Control
| P0091, P00C9
| P0090, P00C8
| P0092, P00CA
| -
|
Circuit/System Description
High pressure fuel is regulated by the high pressure fuel pump actuator, which is a part of the high pressure fuel pump. The high pressure fuel pump actuator is a solenoid valve. The ECM provides battery voltage on the actuator high control circuit and ground on the actuator low control circuit. Both circuits are controlled through output drivers within the ECM. When deactivated, both drivers are disabled. When activated, the high control circuit driver energises the high pressure fuel pump actuator and the low control circuit driver pulse-width modulates (PWM) the low control circuit to ground. The ECM monitors the voltage on the circuits to detect a failure.
Conditions for Running the DTC
• | The ignition voltage is between 11-18 V. |
• | The DTCs run continuously within the enabling conditions. |
Conditions for Setting the DTC
P0090
• | The ECM detects an open circuit in the high pressure fuel pump actuator low control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
P0091
• | The ECM detects a short to ground in the high pressure fuel pump actuator low control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
P0092
• | The ECM detects a short to voltage in the high pressure fuel pump actuator low control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
P00C8
• | The ECM detects an open circuit in the high pressure fuel pump actuator high control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
P00C9
• | The ECM detects a short to ground in the high pressure fuel pump actuator high control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
P00CA
• | The ECM detects a short to voltage in the high pressure fuel pump actuator high control circuit. |
• | The DTC sets when the above condition is present for 4 s. |
Action Taken When the DTC Sets
• | DTCs P0090, P0091, P0092, P00C8, P00C9, and P00CA are Type A DTCs. |
• | A message center or an indicator displays Reduced Engine Power. |
Conditions for Clearing the DTC
DTCs P0090, P0091, P0092, P00C8, P00C9, and P00CA are Type A DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Fuel System Description : LF1
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
- Observe the DTC information with a scan tool. DTC P0090, P0091, P0092, P00C8, P00C9, P00CA, P0685, or P1682 should not set.
- Ignition ON, command the Fuel Pressure Regulator ON and OFF with a scan tool while observing the following control circuit status parameters:
• | Fuel Pressure Regulator Control Circuit High Voltage Test Status |
• | Fuel Pressure Regulator Control Circuit Open Test Status |
• | Fuel Pressure Regulator Control Circuit Low Voltage Test Status |
• | Fuel Pressure Regulator High Control Circuit High Voltage Test Status |
• | Fuel Pressure Regulator High Control Circuit Open Test Status |
• | Fuel Pressure Regulator High Control Circuit Low Voltage Test Status |
⇒ | Each parameter should toggle between OK and Not Run or Not Run and OK. |
- Engine idling, observe the Fuel Rail Pressure Sensor parameter with a scan tool. The pressure should be approximately 1.9-5.0 MPa (276-725 psi).
- Command an increase and decrease in Fuel Pressure with a scan tool. Observe the scan tool Fuel Rail Pressure Sensor parameter. The Fuel Rail Pressure Sensor should increase or decrease with each command.
- 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 G18 high pressure fuel pump.
- Ignition OFF, verify that a test lamp does not illuminate between B+ and the low control circuit terminal 1.
⇒ | If the test lamp illuminates, test the low control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM. |
- Ignition ON, verify that a test lamp does not illuminate between ground and the high control circuit terminal 2.
⇒ | If the test lamp illuminates, test the high control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM. |
- Ignition ON, command the Fuel Pressure Regulator ON with a scan tool. Verify that the test lamp illuminates.
⇒ | If the test lamp does not illuminate, test the high control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM. |
- Ignition OFF, connect a test lamp between the low control circuit terminal 1 and B+.
- Ignition ON, command the Fuel Pressure Regulator ON with a scan tool. Verify that the test lamp illuminates.
⇒ | If the test lamp does not illuminate, test the low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM. |
- If all circuits test normal, test or replace the G18 high pressure fuel pump.
Component Testing
Static Test
- Ignition OFF, disconnect the harness connector at the G18 high pressure fuel pump.
Note: The DMM and test leads must be calibrated to 0 Ω in order to prevent misdiagnosis.
- Test for 9-11 Ω at 25°C (77°F) between the low control circuit terminal 1 and the high control circuit terminal 2.
⇒ | If not within the specified range, replace the G18 high pressure fuel pump. |
- Measure the resistance between each terminal and the high pressure fuel pump housing. The DMM should display OL.
⇒ | If less than the specified value, replace the G18 high pressure fuel pump. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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