Circuit Description
The powertrain control module (PCM) controls the movement of the valve using the exhaust gas recirculation (EGR) control circuit. The PCM monitors the pintle position signal to make sure that the valve responds to the commands from the PCM. With the key turned ON, the PCM learns the EGR closed valve pintle position. When the PCM commands the valve closed, the PCM looks at the difference between the learned closed valve pintle position, and the actual EGR position. If a large difference is present for a certain length of time, the PCM records an error. After the PCM records a calibrated number of consecutive errors, DTC P1404 will set.
Conditions for Running the DTC
| • | System voltage is more than 11.7 volts. |
| • | EGR is enabled. |
Conditions for Setting the DTC
| • | The PCM detects a pintle position more than 8 percent of the learned closed valve position. |
| • | The PCM detects the error for at least 4 consecutive tests. |
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test runs and fails. |
| • | The PCM stores the conditions present when the DTC set as Freeze Frame/Failure Records data. |
Conditions for Clearing the MIL/DTC
| • | The PCM will turn the MIL OFF after the third consecutive trip in which the diagnostic runs and passes. |
| • | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using the scan tool Clear DTC Information function. |
Diagnostic Aids
If the PCM detects a closed valve error, the PCM delays setting DTC P1404 until the valve opens at least 30 percent for 5 seconds between each test. This allows for the possible self-cleaning of the system to remove deposits/corrosion on the valve shaft, or debris from the valve seat.
If the condition is intermittent, refer to Intermittent Conditions in Symptoms.
Inspect for excessive deposits on the EGR valve pintle or seat.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On Board Diagnostic (OBD) System Check? | -- | ||
2 |
Important: If DTC P0403, P0404, and/or P1635 is set, diagnose the applicable DTC first. Refer to Diagnostic Trouble Code (DTC) List/Type . With the engine idling, observe Actual EGR Position display on the scan tool. Is Actual EGR Position at the specified value? | 0% | Go to DTC P0404 Exhaust Gas Recirculation (EGR) Open Position Performance | |
3 |
Does the scan tool indicate that DTC P1404 failed last test? | -- | Go to DTC P0404 Exhaust Gas Recirculation (EGR) Open Position Performance |
