GM Service Manual Online
For 1990-2009 cars only

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 P0090 01: Fuel Pressure Regulator Solenoid 1 Control Circuit Short to Battery

DTC P0090 02: Fuel Pressure Regulator Solenoid 1 Control Circuit Short to Ground

DTC P0090 04: Fuel Pressure Regulator Solenoid 1 Control Circuit Open

DTC P0091: Fuel Pressure Regulator Solenoid 1 Control Circuit Low Voltage

DTC P0092: Fuel Pressure Regulator Solenoid 1 Control Circuit High Voltage

Circuit/System Description

The fuel pressure regulator solenoid 1 is used to control the fuel pressure from the high pressure fuel pump to the fuel rail. The fuel pressure regulator solenoid 1 is pulse width modulated (PWM). An ignition voltage is supplied to the fuel pressure regulator solenoid 1. The ECM controls the solenoid by grounding the control circuit with a solid state device called a driver.

Conditions for Running the DTC

    • The ignition is ON, or the engine is operating.
    • The ignition voltage is less than 16 volts.
    • The DTCs runs continuously once the above conditions are met.

Conditions for Setting the DTC

P0090 02

The ECM detects the fuel pressure regulator solenoid 1 control circuit is open for less than 1 second.

P0090 04, P0091

The ECM detects the fuel pressure regulator solenoid 1 control circuit is shorted to ground for less than 1 second.

P0090 01, P0092

The ECM detects the fuel pressure regulator solenoid 1 control circuit is shorted to voltage for less than 1 second.

Action Taken When the DTC Sets

DTCs P0090, P0091, and P0092 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0090, P0091, and P0092 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Control Module Connector End Views
    •  Engine Controls Connector End Views

Description and Operation

Fuel System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Verification

  1. Ignition ON, observe the DTC information with a scan tool. DTCs P0090, P0091, or P0092 should not set.
  2. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector of the fuel pressure regulator solenoid 1.
  2. Ignition ON, verify a test lamp illuminates between the ignition voltage circuit terminal 1 and ground.
  3. If the test lamp does not illuminate, repair the ignition voltage circuit for a short to ground or an open/high resistance.
  4. Ignition ON, test for 3-4 volts between the control circuit terminal 2 and ground.
  5. If less than the specified range, test for an open or a short to ground on the control circuit. If circuit/connections test normal, replace the ECM.
    If greater than the specified range, test for a short to voltage on the control circuit. If circuit/connections test normal, replace the ECM.
  6. Ignition OFF, test for less than 5 Ohms of resistance between the control circuit terminal 2 and the ECM.
  7. If greater than the specified range, repair the control circuit for a high resistance.
  8. If all circuits/connections test normal, test or replace the fuel pressure regulator solenoid 1.

Component Testing

  1. Measure for 2-4 ohms of resistance between the terminals of the fuel pressure regulator solenoid 1.
  2. If the resistance is not within the specified range, replace the fuel pressure regulator solenoid 1.
  3. Test for infinite resistance between each terminal of the fuel pressure regulator solenoid 1 and the solenoid housing.
  4. If less than infinite resistance, replace the fuel pressure regulator solenoid 1.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Fuel Injection Pump Replacement
    •  Control Module References for ECM replacement, setup, and programming

Repair Verification

Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.

If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning .