DTC Advanced Diagnostics: P049D
DTC P049D:Exhaust Gas Recirculation (EGR) Valve Control Position Exceeded Learning Limit

General Description

The powertrain control module (PCM) controls the exhaust gas recirculation (EGR) valve opening. The system includes the EGR actuator, the EGR valve, the EGR valve position sensor, and the PCM. The EGR valve position sensor is a semiconductor type, and it is attached to the EGR valve and shaft to determine EGR valve position. The EGR valve position signal from the EGR valve position sensor is transmitted to the PCM for target position feedback control. The PCM transmits a signal to the throttle actuator and moves the EGR valve to the fully closed position to register the EGR valve fully closed position when the vehicle is turned to the ON mode or during EGR operation is not in progress. If the registration of the throttle valve fully closed position does not complete within a predetermined time or the registered value is out of predetermined range, the PCM detects a malfunction in the EGR system and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Once per driving cycle
Sequence
None
Duration
–
DTC Type
Two drive cycles, MIL on

Enable Conditions
Condition
Minimum
Maximum
12 volt battery voltage [BATTERY]
10.0 V
–
Vehicle
ON mode
Other
EGR operation not in progress
[ ]: HDS Parameter

Malfunction Threshold
One of these conditions is met:
The registration of the EGR valve fully closed position does not complete within a predetermined time.
The registered value of the EGR valve fully closed position is 1.53 mm (0.0603 in) or more, or -1.66 mm (-0.0654 in) or less.

[ ]: HDS Parameter

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
EGR valve E-EGR line open
EGR valve PG3 line open
EGR valve position sensor failure
EGR valve failure
PCM internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.