The most common issue with the 1404 is the EGR valve.
Roy
DTC P1404
CIRCUIT DESCRIPTION
The exhaust gas recirculation (EGR) valve position sensor is monitored by the powertrain control module (PCM). The 5-volt reference circuit, low reference circuit and the EGR valve position signal circuit are used by the PCM to determine the EGR valve position. When the ignition switch is turned ON, the PCM records the EGR Learned Minimum Position. The PCM compares the EGR Learned Minimum Position parameter to the EGR Position Sensor parameter. If the PCM detects that the EGR valve is still open when the PCM is commanding the EGR valve closed, DTC P1404 sets.
CONDITIONS FOR RUNNING THE DTC
- The engine is running.
- The Ignition 1 Signal voltage parameter is between 11-18 volts.
- The EGR valve is commanded to 0 percent for 20 seconds after the EGR valve has been commanded to open more than 40 percent for 0.5 seconds.
CONDITIONS FOR SETTING THE DTC
- The EGR Position Sensor parameter is 0.2 volt more than the EGR Learned Minimum Position parameter when the Desired EGR Position parameter is commanded to 0 percent for 20 seconds.
- The EGR Position Sensor parameter is more than 40 percent and is steady for 0.5 seconds after a test failure and before the next test will be run.
- The above conditions are met 4 times.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.
DIAGNOSTIC AIDS
- Inspect 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. See: Computers and Control Systems > Initial Inspection and Diagnostic Overview > Intermittent Conditions
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Tuesday, June 18th, 2019 AT 1:38 PM
