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For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2006 🢒 VUE - FWD 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 DTC P0404

Circuit Description

This diagnostic monitors the exhaust gas recirculation (EGR) valve position. The position sensor is mounted within the EGR valve and is part of the EGR valve assembly. A 5-volt reference circuit, low reference circuit, and a signal circuit are used by the powertrain control module (PCM) to determine the EGR valve position. The PCM compares the EGR Position Sensor parameter with the desired EGR Position parameter when the valve is commanded open or closed. If the PCM detects a calibrated difference between the EGR Position Sensor parameter and desired EGR Position parameter for a calibrated amount of time, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0404 Exhaust Gas Recirculation (EGR) Open Position Performance

Conditions for Running the DTC
    • DTC P0030, P0050, P0107, P0108, P0112, P0113, P0117, P0118, P0135, P0155, P0335, P0336, P0401, P0403, P0406, P0641, P0651, P1128, P1129, P2413, P2414, and P2415 are not set.
    • The battery voltage is at least 10.5 volts.
    • The EGR valve is commanded open to at least 0.25 mm (0.010 in).
    • Engine speed is less than 4,000 RPM.
    • DTC P0404 runs once per drive cycle once the above conditions have been met.

Conditions for Setting the DTC
    • The difference between the desired EGR position and the measured EGR position, as determined by the EGR position sensor, is more than 1.020 mm (0.041 in).
    •  The above condition is present for more than 5 seconds.

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 control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

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 excessive deposits on the EGR pintle or seat. Inspect for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.
    • If the condition is intermittent, refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for high resistance in reference voltage circuit. If the test lamp does not illuminates at all, there is excessive resistance in the 5-volt reference circuit or low reference ground circuit.

    2.

  2. This step tests for high resistance in the EGR solenoid control circuit and ground circuits. The PCM provides a 12 volt bias signal on the solenoid control circuit that is pulled low when the solenoid is OK and has a good ground. If the circuit resistance is OK, the DMM should measure ignition voltage.

    3.

  3. After replacing the PCM a new minimum throttle position and idle speed must be established.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Is DTC P0403 or P0406 also set?

--

Go to DTC P0403 or DTC P0406

Go to Step 3

3

  1. Start the engine.
  2. Run the engine until the engine coolant temperature is at least 85°C (185°F).
  3. With the scan tool, command the EGR valve from 0 to 50 percent while observing the EGR Sensor data parameter. Refer to Scan Tool Output Controls .
  4. Command the EGR valve from 50 percent to 100 percent while observing the EGR sensor.

Was the exhaust gas recirculation (EGR) Sensor voltage within the first specified value when at 50 percent and within the second specified value when at 100 percent?

2.10-2.20 V

3.10-3.20 V

Go to Step 4

Go to Step 5

4
  1. Observe the Freeze Frame/Failure Records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. 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 5

Go to Diagnostic Aids

5

  1. Disconnect the EGR valve electrical connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Connect the J 35616-200 Test Lamp between the 5-volt reference circuit of the EGR position sensor and the low reference circuit of the position sensor.

Does the test lamp illuminate at least dimly?

--

Go to Step 6

Go to Step 7

6
  1. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the EGR position sensor and the sensor signal circuit.
  2. Observe the EGR Sensor parameter on the scan tool.

Is the EGR sensor voltage near the specified value?

4.96 V

Go to Step 8

Go to Step 12

7

Connect the test lamp between the 5-volt reference circuit of the EGR valve and a good ground.

Does the test lamp illuminate at least dimly?

--

Go to Step 11

Go to Step 13

8

  1. At the EGR valve electrical connector, connect a DMM between the EGR solenoid control circuit and the EGR solenoid ground circuit.
  2. Turn ON the ignition, with the engine OFF.

Is the voltage near the specified value?

12 V

Go to Step 10

Go to Step 9

9

Connect the DMM between the EGR solenoid control circuit and a known good ground.

Is the voltage near the specified value?

12 V

Go to Step 15

Go to Step 14

10
  1. Remove the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement .
  2. Inspect the EGR valve pintle and seat area for foreign debris. Remove as necessary.

Did you find and correct the condition?

--

Go to Step 20

Go to Step 16

11

Test the low reference circuit of the EGR position sensor for high resistance. Refer to Exhaust Gas Recirculation Valve Replacement .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

12

Test the EGR position sensor signal circuit for the following conditions:

    • An open
    • A short to ground
    • High resistance

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

13

Test the 5-volt reference circuit of the EGR position sensor for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

14

Test the control circuit of the EGR valve for resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

15

Repair the condition of high resistance in the ground circuit of the EGR valve. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

--

Go to Step 20

--

16

Test for an intermittent and for a poor connection at the EGR valve. Refer to Testing for Intermittent Conditions and Poor Connections Connector Repairs .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 18

17

Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 20

Go to Step 19

18

Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement .

Did you complete the replacement?

--

Go to Step 20

--

19

  1. Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
  2. Perform the idle learn procedure. Refer to Idle Learn .

Did you complete the replacement?

--

Go to Step 20

--

20
  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 21

21

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK