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 DTC P0400 [MZR-CD (RF Turbo)]

DTC P0400 [MZR-CD (RF Turbo)]

id0102f1954600

DTC P0400

EGR flow problem

DETECTION CONDITION

• The PCM monitors the EGR valve driving duty value after the engine starts. If the EGR valve driving duty value is more than 80 %, the PCM determines that the EGR recirculation flow is malfunction.
Diagnostic support note
• MIL illuminates if PCM detects above malfunction condition in two consecutive drive cycles or in one drive cycle while DTC for the same malfunction has been stored in PCM.
• PENDING CODE is available if PCM detects the above malfunction condition during first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• EGR valve malfunction (stuck)
• EGR valve position sensor malfunction
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record FREEZE FRAME DATA on repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Check for related service repair information availability?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is DTC P0400 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to troubleshooting procedures for DTC in FREEZE FRAME DATA.
4
INSPECT EGR VALVE OPERATION
• Perform the EGR Valve Operation Inspection.
• Does EGR valve operate properly?
Yes
Go to the next step.
No
Repair or replace malfunctioning part, according to inspection results.
Then go to Step 6.
5
INSPECT EGR VALVE POSITION SENSOR
• Access EGRP PID with % and V mode.
• Turn the engine switch to the ON position (engine off).
• Move the EGR valve using EGRP PID % mode simulation function.
• Monitor EGRP PID V mode.
• Does EGRP PID V mode moves according to EGR valve actuate value?
Yes
Go to the next step.
No
Inspect the EGR valve position sensor.
• If the EGR valve position sensor normal, go to the next step.
• If the EGR valve position sensor not normal, replace the EGR valve.
Then go to the next step.
6
VERIFY TROUBLESHOOTING OF DTC P0400 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Turn the engine switch to ON position (engine off).
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
7
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Is any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.