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DTC P049B:00 [PCM (SKYACTIV-D)]

DTC P049B:00 [PCM (SKYACTIV-D)]


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Note
•  To determine the malfunctioning part, proceed with the diagnostics from “Function Inspection Using M-MDS”.

Details On DTCs

Description

LP-EGR flow insufficient detected

Detection condition
Determination conditions
•  When the following condition is met, the LP-EGR volume is lower than the specification for 0.30 g/rev for a continuous 8.2 s.
Preconditions
•  During LP-EGR control
•  During HP-EGR control
•  Fuel injection amount:15—50 mm3/stoke
•  Engine speed: 1,300—6,000 rpm
•  Engine torque: 70—240 N·m{7.2—24 kgf·m, 52—177 ft·lb}
•  Target HP-EGR flow volume: 0.31―0.6 g/rev
•  The following DTCs are not detected:
―  MAP sensor: P0105:00, P0106:00, P0107:00, P0108:00
―  MAF sensor: P0102:00, P0103:00
―  Exhaust gas pressure sensor No.1: P0470:00, P0471:00, P0472:00, P0473:00
―  Exhaust gas temperature sensor No.1: P0545:00, P0546:00
―  Intake shutter valve control: P2101:00, P2118:00, P1589:00
―  Intake shutter valve position sensor: P0122:00, P0123:00
―  HP-EGR control valve DC motor control system: P0404:00
―  HP-EGR control valve position sensor: P0405:00, P0406:00
―  LP-EGR control valve DC motor control system: P0488:00, P045B:00, P213B:00
―  LP-EGR control valve position sensor: P0407:00, P0408:00
―  Exhaust shutter valve DC motor control system: P0475:00, P0476:00
―  Exhaust shutter valve position sensor: P048D:00, P048E:00
―  IAT sensor No.3: P1118:00, P1119:00, P1147:00
Drive cycle
•  2
Self test type
•  CMDTC self test
Sensor used
•  LP-EGR control valve
•  HP-EGR control valve
•  Intake shutter valve
•  Exhaust shutter valve
•  MAF sensor
•  MAP sensor
•  Boost air temperature sensor
•  Exhaust gas pressure sensor No.1
•  Exhaust gas temperature sensor No.1 etc.
Fail-safe
•  Not applicable
Vehicle status when dtcs are output
•  Check engine light is illuminated
Possible cause
•  Erratic signal to PCM
―  MAF sensor signal malfunction
―  MAP sensor signal malfunction
―  Boost air temperature sensor signal malfunction
―  Exhaust gas pressure sensor signal malfunction
―  Exhaust gas temperature sensor No.1 signal malfunction
―  Input signal part connector or terminals malfunction
―  Input signal part related circuit malfunction
•  HP-EGR system malfunction
•  Exhaust shutter valve malfunction
•  LP-EGR control valve malfunction (stuck close)
•  Exhaust shutter valve position sensor (built-into exhaust shutter valve) malfunction
•  LP-EGR control valve position sensor (built-into LP-EGR control valve) malfunction
•  EGR cooler clogged
•  Catalytic converter or diesel particulate filter malfunction (deformation, damage)
•  Exhaust gas leakage from LP-EGR system
•  LP-EGR system passage malfunction (restriction)
•  Air suction in intake air system between turbocharger and intake manifold
•  PCM malfunction


System Wiring Diagram

•  Not applicable

Function Explanation (DTC Detection Outline)

•  The PCM performs diagnosis of the LP-EGR system by comparing the target EGR volume with the actual.
•  The PCM monitors the flow volume during LP-EGR implementation.
•  The PCM calculates the difference between the target EGR flow volume and the actual EGR flow volume during LP-EGR implementation. If the monitored, actual flow volume is lower than the specification for the target flow volume, the PCM determines that there is inadequate flow volume.
•  The PCM performs diagnosis when each of the preconditions during drive cycle is met. If a malfunction is detected, the malfunction detection counter begins counting up. The value of the malfunction detection counter is maintained while the preconditions are not being met. If the cumulative value of the malfunction detection counter exceeds the threshold during the first drive cycle, a malfunction is determined and a pending code is stored.
•  If the calculated value of the malfunction detection counter during one drive cycle exceeds the threshold, the PCM determines a malfunction, stores a DTC and turns on the check engine light.
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Repeatability Verification Procedure

Caution
•  When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
•  While performing this step, always operate the vehicle in a safe and lawful manner.
1.  Start the engine and warm it up completely.
2.  Drive the vehicle for 1 min at a speed of 100 km/h {62.2 mph} or more.
3.  Repeat Step 2 operation above 2 times.

PID Item/Simulation Item Used In Diagnosis

PID/DATA monitor item table

Item (definition)

Reference

CHARGE_AIR_COOL_TEMP
EX_PRES
EX_GAS_TEMP_1
MAP
MAF


Function Inspection Using M-MDS

Step

Inspection

Results

Action

1
PURPOSE: VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY
•  Verify related Service Bulletins, on-line repair information, or Service Information availability.
•  Is any related Information available?
Yes
Perform repair or diagnosis according to the available information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
2
PURPOSE: VERIFY DTC CAUSING FREEZE FRAME DATA
•  Is DTC P049B:00 causing the freeze frame data?
Yes
Go to the next step.
No
Inspect the DTC causing the freeze frame data.
3
PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION
•  Record the freeze frame data/snapshot data.
Note
•  Recording can be facilitated using the screen capture function of the PC.
Go to the next step.
4
PURPOSE: VERIFY OTHER RELATED DTCs
•  Perform the DTC inspection for the PCM.
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
Go to the next step.
5
PURPOSE: VERIFY IF THERE IS PID ITEM CAUSING DRASTIC CHANGES OF ACCELERATION FLUCTUATION BY INPUT SIGNAL TO PCM
•  Access the following PIDs using the M-MDS:
PCM:
―  EX_PRES
―  EX_GAS_TEMP_1
―  CHARGE_AIR_COOL_TEMP
―  MAF
―  MAP
•  Is there any signal that is far out of specification?
Yes
Go to the next step.
No
Go to Troubleshooting Diagnostic Procedure to perform the procedure from step 1.
6
PURPOSE: VERIFY CONNECTOR CONNECTIONS
•  Access the following PIDs using the M-MDS:
PCM:
―  EX_PRES
―  EX_GAS_TEMP_1
―  CHARGE_AIR_COOL_TEMP
―  MAF
―  MAP
•  When the following parts are shaken, does the PID value include a PID item which has changed?
―  Exhaust gas pressure sensor No.1
―  Exhaust gas temperature sensor No.1
―  Boost air temperature sensor
―  MAF sensor
―  MAP sensor
―  PCM
Yes
Repair or replace the applicable connector parts.
Go to the troubleshooting procedure to perform the procedure from repair completion verification.
No
Go to Troubleshooting Diagnostic Procedure to perform the procedure from step 1.


Troubleshooting Diagnostic Procedure

Intention of troubleshooting procedure
•  Step 1—3
―  Perform inspection of each separate part.
•  Step 4—8
―  Perform inspection of HP-EGR and LP-EGR passage
•  Repair completion verification
―  Verify that the primary malfunction is resolved and there are no other malfunctions.

Step

Inspection

Results

Action

1
PURPOSE: IINSPECT EXHAUST SHUTTER VALVE POSITION SENSOR FOR MALFUNCTION
•  Is the part normal?
Yes
Go to the next step.
No
Inspect the exhaust shutter valve, then go to repair completion verification.
2
PURPOSE: INSPECT LP-EGR CONTROL VALVE CONTROL SYSTEM OPERATION
•  Perform the LP-EGR Control Valve Operation Inspection.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
No
Go to the next step.
3
PURPOSE: IINSPECT LP-EGR CONTROL VALVE POSITION SENSOR FOR MALFUNCTION
•  Inspect the applicable part.
•  Is the part normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
4
PURPOSE: INSPECT INTAKE AIR SYSTEM FOR AIR SUCTION
•  Inspect for air leakage at the following:
―  Around connection of turbocharger and intake manifold
Note
•  Engine speed may change when rust penetrating agent is sprayed on the air suction area.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
No
Go to the next step.
5
PURPOSE: INSPECT FOR RESTRICTION OR CLOGGED IN HP-EGR PASSAGE
•  Switch the ignition off.
•  Remove the HP-EGR control valve.
•  Visually inspect the HP-EGR passage for clogging and the gasket correctly installed.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
(If there is clogging caused by soot in the HP-EGR control valve, inspect around the HP-EGR piping and clean or replace it.)
No
Go to the next step.
6
PURPOSE: INSPECT EGR COOLER
•  Inspect the EGR cooler for clogging.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
No
Go to the next step.
7
PURPOSE: INSPECT LP-EGR SYSTEM FOR LEAKAGE
•  Visually inspect for exhaust gas leakage from the LP-EGR system.
•  Is there any leakage?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to repair completion verification.
No
Go to the next step.
8
PURPOSE: INSPECT FOR RESTRICTION IN LP-EGR SYSTEM PASSAGE
•  Switch the ignition off.
•  Remove the LP-EGR control valve.
•  Visually inspect the LP-EGR passage for restriction and the gasket correctly installed.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
(If there is restriction caused by soot in the LP-EGR control valve, inspect around the LP-EGR piping and clean or replace it.)
No
Go to the next step.
Repair completion verification 1
PURPOSE: VERIFY THAT VEHICLE IS REPAIRED
•  Install/connect the part removed/disconnected during the troubleshooting procedure.
•  Clear the DTC recorded in the memory.
•  Replicate the vehicle conditions at the time the DTC was detected using the following procedure.
―  Implement the repeatability verification procedure.
•  Perform the DTC inspection for the PCM.
•  Is the same Pending DTC present?
Yes
Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
If the CAN communication is normal, perform the diagnosis from Step 1.
•  If the malfunction recurs, replace the PCM, then go to the next step.
No
Go to the next step.
Repair completion verification 2
PURPOSE: VERIFY IF OTHER DTCs DISPLAYED
•  Perform the DTC inspection.
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
DTC troubleshooting completed.