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Home >> Mazda >> 2016 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic (2 Of 4) >> DTC P0401-00: EGR Flow Insufficient Detected >> Function Inspection Using M-MDS
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Function Inspection Using M-MDS

STEP INSPECTION ACTION
1 PURPOSE: RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION 
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
- Go to the next step.
2 PURPOSE: VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
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 PURPOSE: IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is the DTC P0401:00 on FREEZE FRAME DATA?
Yes Go to the next step.
No Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA.
(Refer to DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
4 PURPOSE: VERIFY IF DIAGNOSTIC RESULT IS AFFECTED BY OTHER RELATED DTCs OCCURRING 
Yes Go to the applicable DTC inspection.
(Refer to DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
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 
Yes Go to the next step.
No Go to the troubleshooting procedure to perform the procedure from Step 1.
6 PURPOSE: VERIFY CONNECTOR CONNECTIONS 
  • Access the following PIDs using the M-MDS:

    (Refer to ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)

    PCM: 

    • MAF
    • MAP
    • MAP_V
  • When the following parts are shaken, does the PID value include a PID item which has changed?
    • MAF sensor
    • MAP sensor
    • PCM
Yes Repair or replace the applicable connector parts.
Go to the troubleshooting procedure to perform the procedure from Step 5.
No Go to the troubleshooting procedure to perform the procedure from Step 1.