P1404

DTC P1404

CIRCUIT DESCRIPTION
The engine control module (ECM) controls the EGR valve opening based on the atmospheric pressure, engine speed, engine coolant temperature, intake air temperature and fuel injection quantity. The ECM controls the EGR valve by controlling the EGR DC motor. The EGR valve position is detected by the EGR position sensor, and relayed to ECM. If the ECM detects a difference between the learned closed position and the commanded closed position for a calibrated amount of time, this DTC will set.

Condition for Running the DTC
- DTCs P0112, P0113, P0116, P0117, P0118, P0403, P0405, P0406, P0642, P0643, P2227, P2228 and P2229 are not set.
- The ignition switch is ON for 2 seconds.
- The desired EGR valve position is stable.

Condition for Setting the DTC
- The ECM detects that the EGR learned minimum position is more than 5mm and actual EGR valve position is more than 5% for 3 seconds.

OR
- The ECM detects that the EGR learned minimum position is less than -5mm and actual EGR valve position is more than 5% for 3 seconds.

Action Taken When the DTC Sets
- The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive driving cycle 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 Freeze Frame/Failure Records on the second consecutive driving cycle when the diagnostic runs and fails.

Condition for Clearing the MIL/DTC
- The ECM turns OFF the MIL after 3 consecutive driving cycles when the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes after the key is cycled.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic after the ECM turns OFF the MIL.
- Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
- A sticking or intermittently sticking the EGR valve may set this DTC.

If an intermittent condition is suspected, the following may cause an intermittent:
- Faulty EGR valve
- Poor connections
- Misrouted harness
- Rubbed through wire insulation
- Broken wire inside the insulation

Check for the following conditions:
- Poor connection at the ECM: Inspect 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. If the harness appears to be OK, observe the "EGR Current Position" display on the scan tool with engine running while moving connectors and wiring harness. A change in the display will indicate the location of the fault.

Test Description
The number below refers to the step number on the diagnostic table.
8. Operate the vehicle within the same conditions as when the DTC failed. If you can not duplicate this DTC, use the information in the Freeze Frame/Failure Records data can help to locate an intermittent condition.

DTC P1404
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views

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