P0404
DTC P0404
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. The PCM compares the EGR Position Sensor parameter with the Desired EGR Position parameter when the valve is commanded open or closed. If the PCM detects a calibrated difference between the EGR Position Sensor parameter and Desired EGR Position parameter for a calibrated amount of time, when the EGR valve is commanded open, DTC P0404 sets.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0404 Exhaust Gas Recirculation (EGR) Open Position Performance
CONDITIONS FOR RUNNING THE DTC
- DTCs P0641 and P0651 are not set.
- The Ignition 1 Signal parameter is more than 11 volts.
- The engine is running.
- The EGR command will be disabled if the Startup ECT parameter is less than 5°C (41°F) and will not enable until the ECT Sensor parameter is more than 75°C (167°F).
- The EGR valve is commanded to open.
- DTC P0401 is not active.
- The Desired EGR Position parameter is more than 0 percent.
- The Desired EGR Position parameter does not change more than 30 percent for longer than 1 second.
- The EGR valve is not being commanded with a scan tool.
- DTC P0404 runs continuously once the above conditions are met.
CONDITIONS FOR SETTING THE DTC
The difference between the EGR Position Sensor parameter and the Desired EGR Position parameter is more than 15 percent for longer than 100 seconds.
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 pintle or seat. Inspect for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.
- If the condition is intermittent, refer to Intermittent Conditions. Intermittent Conditions
TEST
Steps 1-8:
Steps 9-13:
