P1404

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Engine Controls Schematics: PCM Emission Inputs:

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. 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
The system voltage is more than 10 volts.

CONDITIONS FOR SETTING THE DTC
^ EGR feedback is 0.5 volt more than the EGR Closed Valve Pintle Position when the Desired EGR Position is commanded to 0 percent.
^ The above condition is present for longer than 20 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
^ The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Freeze Frame and/or the Failure Records.

The PCM will disable EGR for the ignition cycle.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM turns the MIL OFF after three 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 forty 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 (PCM) Description, Clearing Diagnostic Trouble Codes.

DIAGNOSTIC AIDS

NOTE: Refer to Connector Test Adapter Kit J 35616-A Notice in Service Precautions.

Check for 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.

If the problem is intermittent, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. This step verifies that the malfunction is present.
4. If DTC P1404 will only set under certain conditions, the malfunction may be intermittent. Refer to Diagnostic Aids. If an intermittent problem is suspected, check for poor connections at the PCM or the EGR valve. If the wiring and connections are OK and DTC P1404 continues to set, replace the EGR valve.
14. 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.