For 1990-2009 cars
Engine Controls Components
Power, Ground, MAF, EVAP, and EGR
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

### Circuit Description

The powertrain control module (PCM) monitors the EGR valve pintle position input to ensure that the valve responds properly to commands from the PCM. When the ignition switch is turned ON, the PCM learns the EGR closed valve pintle position. The PCM compares the learned EGR closed valve pintle position to the Actual EGR position when the EGR valve is commanded closed. If the Actual EGR position indicates that the EGR valve is still open when the PCM is commanding the EGR valve closed, DTC P1404 will set.

### Conditions for Running the DTC

• | TP, VSS, Misfire, IAT, MAP, Idle Speed, Fuel Injector, ECT, CKP, or MAF Sensor DTCs are not set.

• | System voltage is between 9.0-18.0 volts.

### Conditions for Setting the DTC

• | EGR Feedback is 0.4 volt more than the EGR Closed Valve Pintle Position when the Desired EGR Position is commanded to 0 percent.

• | The above condition has to be present twice.

### Action Taken When the DTC Sets

• | The PCM will illuminate the malfunction indicator lamp (MIL) during the first trip in which the diagnostic test has been run and failed.

• | The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.

### Conditions for Clearing the MIL/DTC

• | The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.

• | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

• | The DTC can be cleared by using a scan tool.

### Diagnostic Aids

Inspect for the following conditions:

Excessive deposits on the EGR valve pintle or seat -- Remove the EGR valve and check for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.

Many situations may lead to an intermittent condition. Perform each inspection or test as directed.

Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

• | Loose terminal connection

- | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.

- | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.

• | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.

• | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.

If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.

### Test Description

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

1. This step verifies that the malfunction is present.

2. If DTC P1404 will only set under certain conditions, the malfunction may be intermittent; refer to DTC P1404 Diagnostic Aids. If an intermittent wiring problem is not present, check for a poor connection at the PCM or the EGR valve. If the connections are OK and DTC P1404 continues to set, replace the EGR valve.

3. This step ensures that the replacement PCM, which utilizes an electrically erasable programmable read only memory (EEPROM), is programmed when installed.

#### DTC P1404 - EGR Valve Stuck Open Table

Step | Action | Values | 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 | Important: If DTC P0403 is set, diagnose the DTC P0403 Exhaust Gas Recirculation (EGR) Solenoid Control Circuit first. Refer to DTC P0403 Exhaust Gas Recirculation (EGR) Solenoid Control Circuit . With the engine idling, observe Actual EGR Position display on the scan tool.

Is the Actual EGR Position at the specified value?

0%

Go to Step 3

Go to Step 5

3 |

1. Turn ON the ignition.
2. Select the scan tool EGR valve output control function.
3. Increment the EGR valve through all positions 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 4

Go to Step 6

4 |

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 P1404 until the DTC P1404 test runs.

Does the scan tool indicate DTC P1404 failed this ignition?

--

Go to Step 5

Go to Diagnostic Aids

5 |

1. Disconnect the EGR valve electrical connector.
2. Observe Actual EGR Position on the scan tool.

Is the Actual EGR Position at the specified value?

0%

Go to Step 6

Go to Step 7

6 | Probe the EGR pintle position sensor ground circuit at the EGR valve harness connector with a test lamp to battery positive voltage. Does the test lamp illuminate? | -- | Go to Step 9 | Go to Step 8
7 |

1. Turn OFF the ignition.
2. Disconnect the PCM.
3. Turn ON the ignition.
4. Using a DMM, measure voltage between the EGR valve pintle position signal circuit and ground.

Is the measured voltage near the specified value?

0.0 V

Go to Step 12

Go to Step 11

8 |

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

Did you find and correct the condition?

--

Go to Step 15

Go to Step 13

9 |

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

Did you find and correct the condition?

--

Go to Step 15

Go to Step 10

10 | Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement . Notice: In order to prevent further damage if the EGR valve shows signs of excessive heat, check 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; one of which might be an injector which is open due to one of the following reasons:

• | Stuck

• | Grounded driver circuit

Check the oil for possible fuel contamination if a stuck open fuel injector is found.

Is the action complete?

--

Go to Step 15

--

11 | Locate and repair short to voltage in the EGR pintle position signal circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 15 | --
12 |

1. Check for the following conditions:

• | The EGR valve pintle position signal circuit for a short to the 5 volt reference circuit.

• | The EGR valve pintle position signal circuit for a short to the EGR valve control circuit.

2. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 14

13 |

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

Did you find and correct the condition?

--

Go to Step 15

Go to Step 14

14 | Important : The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Is the action complete? | -- | Go to Step 15 | --
15 |

1. Review and record scan tool Failure Records data.
2. Clear the DTCs.
3. Operate the vehicle within Failure Records conditions.
4. Using a scan tool, monitor Specific DTC info for DTC P1404.

Does the scan tool indicate DTC P1404 failed this ignition?

--

Go to Step 2

System OK