GM Service Manual Online
For 1990-2009 cars only

DTC P0092 Without RPO CTF

Circuit Description

The pressure control (PC) valve is used to adjust supply pump discharge amount so as to adjust common rail pressure. The discharge amount from the supply pump to the common rail is determined by PC valve current timing.

Conditions for Running the DTC

    • Battery voltage is more than 10 volts.
    • The engine is running.

Conditions for Setting the DTC

Abnormally high driving voltage with the PC valve ON, the pump is in normal mode, and the battery voltage is higher than 10 volts when the ignition is ON.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The ECM limits fuel delivery.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

Inspect for the following conditions:

    • Poor connection at the ECM
        Inspect the harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection.
    • Damaged harness
        Inspect the wiring harness for damage, shorts to ground, shorts to battery, and open circuits. If the harness appears to be OK, observe the PC valve display on the scan tool while moving connectors and wiring harnesses related to the PC valve sensor. A change in the PC valve scan tool display will indicate the location of the fault.

Step

Action

Value

Yes

No

Schematic Reference: Engine Controls Schematics

1

Does the DTC set with the engine running?

--

Go to Step 2

Go to Diagnostic Aids

2

  1. Turn OFF the ignition.
  2. Disconnect pressure control (PC) valve 1 and PC valve 2 connectors.
  3. Measure the resistance between pin number 1 and 2 on the PC valve 1.

Does the resistance measure within the specified range?

0.9-1.3 ohms

Go to Step 3

Go to Step 7

3

  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM) connector. The PC valve connector remains connected.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure voltage between pin number CS-1 of the PC valve 1 and pin number C2-8 of the ECM harness.

Does the voltage measure less than the specified value?

1 V

Go to Step 5

Go to Step 4

4

Repair the short to battery voltage on the PC valve control circuit to the ECM on the PC valve harness.

Did you complete the repair?

--

Go to Step 10

--

5

  1. Turn OFF the ignition.
  2. Reconnect all connector to the ECM and PC valves.
  3. Turn ON the ignition.
  4. Clear the DTCs.

Does The DTC reset?

--

Go to Step 8

Go to Step 6

6

  1. Turn OFF the ignition.
  2. Disconnect the PC valve harness from the PC valve, the PC valve relay and the ECM.
  3. Measure the voltage between pin number 1 at the PC valve relay of the PC valve harness and pin number C2-8 at the ECM .

Does the voltage measure less than the specified value?

1 V

Go to Step 10

Go to Step 9

7

Replace the PC valve assembly.

Did you complete the replacement?

--

Go to Step 10

--

8

Replace the ECM.

Did you complete the replacement?

--

Go to Step 10

--

9

Repair/replace the PC valve harness.

Did you complete the action?

--

Go to Step 10

--

10

Clear all DTCs.

Does the DTC reset?

--

Go to Step 1

Go to Step 11

11

Operate the vehicle.

Do any other DTCs set?

--

Go to Diagnostic Trouble Code (DTC) List

System OK

DTC P0092 With RPO CTF

Circuit Description

The suction control valve (SCV) is on the fuel supply pump and controls the suction fuel quantity to the fuel rail. The SCV is fully opened in normal state, and increased drive current results in closing the orifice. The engine control module (ECM) calculates the desired fuel rail pressure and fuel flow rate, and compares the desired fuel rail pressure to the actual rail pressure to determine the SCV position. When the actual fuel rail pressure is higher than the desired value, the SCV is closed to decrease the flow rate. If the ECM detects an excessively high SCV solenoid drive current, this DTC will set.

Conditions for Running the DTC

    • The ignition is ON.
    • The battery voltage is between 10-16 volts.
    • The fuel supply pump is normal.
    • The SCV operating duty is between 20-50 percent.
    • The deviation of the SCV operating duty is less than 10 percent.

Conditions for Setting the DTC

The SCV solenoid operating current is more than 2700 mA.

Action Taken When the DTC Sets

    • The ECM illuminates the malfunction indicator lamp (MIL) and reduced engine power indicator lamp, if equipped, when the diagnostic runs and fails.
    • The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records.
    • The ECM limits accelerator operating range.
    • The ECM limits fuel injection quantity.
    • The ECM limits fuel rail pressure.
    • The ECM closes the exhaust gas recirculation (EGR) valve and stops the EGR control.
    • The ECM inhibits cruise control.

Conditions for Clearing the DTC

    • The MIL resets when the ignition is turned OFF.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check - Engine Controls?

--

Go to Step 1

Go to Diagnostic System Check - Engine Controls

2

  1. Observe the Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Does the DTC fail this ignition?

--

Go to Step 3

Go to Intermittent Conditions

3

  1. Turn OFF the ignition.
  2. Disconnect the suction control valve (SCV).
  3. Measure the resistance of the SCV solenoid coil.

Is the resistance within the specified range?

1.9-2.3 ohms at 20°C (68°F)

Go to Step 4

Go to Step 7

4

  1. Test the power supply circuits between the engine control module (ECM) and the SCV for a short to battery voltage circuit.
  2. Repair the circuits, as necessary.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 5

5

  1. Test the signal circuits between the ECM and the SCV for a short to voltage circuit.
  2. Repair the circuits, as necessary.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 6

6

  1. Turn OFF the ignition.
  2. Disconnect the ECM.
  3. Inspect for poor connections at the harness connector of the ECM.
  4. Repair the connections, as necessary.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

7

Important: The SCV is part of the fuel supply pump.

Replace the fuel supply pump. Refer to Fuel Injection Pump Replacement .

Did you complete the replacement?

--

Go to Step 9

--

8

Important: The new ECM must be programmed.

Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data .

Did you complete the replacement?

--

Go to Step 9

--

9

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 10

10

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK