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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2000 🢒 Intrigue 🢒 Engine 🢒 Engine Controls - 3.5L 🢒 DTC P0405 Exhaust Gas Recirculation (EGR) Position Sensor Circuit Low Voltage

Refer to

PCM Emission Inputs


Object Number: 590102 Size: FS
Engine Emissions Fuses
Engine Emissions Fuses
Handling ESD Sensitive Parts Notice
Engine Controls Component Views
Powertrain Control Module Description
PCM Engine Oil Level and Pressure Inputs
PCM Fuel Tank Inputs
OBD II Symbol Description Notice
 in Engine Controls Schematics .

Circuit Description

The powertrain control module (PCM) monitors the exhaust gas recirculation (EGR) valve pintle position input to ensure that the valve responds properly to commands from the PCM and to detect a fault if the pintle position sensor circuit is open or shorted. If the PCM detects an excessively low EGR feedback signal voltage, DTC P0405 will set.

Conditions for Running the DTC

System voltage is more than 10 volts.

Conditions for Setting the DTC
    • EGR feedback is less than 0.14 volt at any time.
    • The condition is present for longer than 20 seconds.

Conditions for Clearing the MIL/DTC
    • The PCM turns the MIL OFF after 3 consecutive drive trips during which the diagnostic runs and passes.
    • A last test failed, or the current DTC, clears when the diagnostic runs and passes.
    • A History DTC clears after 40 consecutive warm-up cycles, if no other emission related diagnostic failures are reported.
    • Use a scan tool in order to clear the MIL diagnostic trouble code.
    • Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes.

The PCM will disable EGR for the rest of the ignition cycle.

Action Taken When the DTC Sets
    • The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

Diagnostic Aids

Notice: Use the connector test adapter kit J 35616-A for any test that requires probing the following items:

   • The PCM harness connectors
   • The electrical center fuse/relay cavities
   • The component terminals
   • The component harness connector
Using this kit will prevent damage caused by the improper probing of connector terminals.

If the problem is intermittent, refer to Intermittent Conditions .

Test Description

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

  1. This step verifies that the malfunction is present.

    2.

  2. If DTC P0405 will only set under certain conditions, the malfunction may be intermittent. Refer to Diagnostic Aids.

    3.

  3. This vehicle is equipped with a PCM which utilizes an electrically erasable programmable read only memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Turn the key to ON with the engine OFF.
  2. Select the scan tool EGR valve output control function.
  3. Increment the EGR valve from 0 percent to 100 percent while comparing Desired EGR Position to Actual EGR Position.

Does Desired EGR Position remain close to Actual EGR Position at all commanded positions?

--

Go to Step 3

Go to Step 4

3

  1. Review and record scan tool Failure Records data.
  2. Operate the vehicle within Failure Records conditions.
  3. Using a scan tool, monitor Specific DTC info for DTC P0405.

Does the scan tool indicate DTC P0405 failed this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4
  1. Disconnect the EGR valve electrical connector.
  2. Connect the DMM to measure voltage between the EGR pintle position sensor ground circuit and the 5 volt reference A circuit at the EGR valve connector.

Is the voltage at the specified value?

5V

Go to Step 5

Go to Step 9

5

Probe the EGR valve pintle position circuit at the EGR valve harness connector with a test lamp connected to B+.

Is the test lamp ON?

--

Go to Step 8

Go to Step 6

6
  1. Connect a jumper between the 5 volt reference circuit and the pintle position circuit at the EGR valve connector.
  2. Observe Actual EGR Position on the scan tool.

Is Actual EGR Position at the specified value?

100%

Go to Step 13

Go to Step 7

7
  1. Turn the key to OFF.
  2. Disconnect the PCM.
  3. Check for an open in the EGR valve pintle position circuit.
  4. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 19

Go to Step 17

8
  1. Turn the key to OFF.
  2. Disconnect the PCM.
  3. Probe the EGR valve pintle position circuit with a test lamp to B+.

Is the test lamp ON?

--

Go to Step 12

Go to Step 15

9

Probe the 5 volt reference circuit with a test lamp to B+.

Is the test lamp ON?

--

Go to Step 10

Go to Step 11

10
  1. Turn the key to OFF.
  2. Disconnect the PCM.
  3. Probe the 5 volt reference circuit with a test lamp to B+.

Is the test lamp ON?

--

Go to Step 16

Go to Step 17

11
  1. Check for an open in the 5 volt reference circuit between the PCM and the EGR valve.
  2. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 19

Go to Step 17

12

Locate and correct the short to ground in the EGR valve pintle position circuit. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 19

--

13
  1. Check for the following conditions:
    2. • Poor terminal connections at the EGR valve
    • The EGR pintle position signal circuit shorted to the EGR valve control circuit
  2. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 19

Go to Step 14

14

Notice: If the EGR valve shows signs of excessive heat, inspect the exhaust system for blockage--possibly a plugged converter--using the procedure found on the Restricted Exhaust System Check. If the exhaust system is restricted, repair the cause. Inspect for an open injector caused by one or more of the following conditions:

   • Stuck
   • Grounded driver circuit
   • Possible faulty control module
If one of the above conditions is found, inspect the oil for possible fuel contamination.

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

Is the action complete?

--

Go to Step 19

--

15
  1. Check the EGR valve pintle position circuit for a short to the sensor ground circuit.
  2. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 19

Go to Step 17

16

Locate and repair short to ground in the 5 volt reference A circuit. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 19

--

17
  1. Check the circuits related to the EGR valve for a poor terminal connection at the PCM.
  2. If a problem is found, repair as necessary. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 19

Go to Step 18

18

Important:: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 19

--

19
  1. Clear the DTCs with the scan tool.
  2. Turn the key to OFF and wait 15 seconds.
  3. Operate the vehicle within the conditions that are required for this diagnostic to run. Refer to the Conditions for Running the DTC.

Does the scan tool indicate that this test ran and passed?

--

Go to Step 20

Go to Step 2

20

Review Captured Info using the scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to the applicable DTC table

System OK