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Home >> Mazda >> 2017 >> CX-5 Touring, FWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (1 Of 5) >> DTC P0300-00: Random Misfire Detected >> Function Inspection Using M-MDS
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Function Inspection Using M-MDS

STEP INSPECTION RESULTS ACTION
1 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.
2 PURPOSE: IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
  • Is the DTC P0300:00 on FREEZE FRAME DATA?
Yes Go to the next step.
No Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA.
(See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
3 PURPOSE: RECORD FREEZE FRAME DATA/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS 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 and DIAGNOSTIC MONITORING TEST RESULTS (misfire related) on the repair order.
- Go to the next step.
4 PURPOSE: VERIFY RELATED PENDING CODE AND/OR DTC Yes Go to the applicable PENDING CODE or DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
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 Inspect the suspected sensor and related wiring harness.
  • If there is any malfunction:
    • Repair or replace the malfunctioning part.
      • Go to the troubleshooting procedure to perform the procedure from Step 10.
  • If there is no malfunction:
    • Go to the next step.
No Go to the next step.
6 PURPOSE: RECORD NUMBER OF CURRENT MISFIRES DURING NO LOAD TO SPECIFY MISFIRING CYLINDER Yes Record each of the verified values, then go to the next step.
No Go to step 9.
7 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD SPARK PLUGS Yes Go to the troubleshooting procedure to perform the procedure from Step 1.
No Go to the next step.
8 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD IGNITION COIL Yes Go to the troubleshooting procedure to perform the procedure from Step 2.
No Go to the troubleshooting procedure to perform the procedure from Step 3.
9 PURPOSE: RECORD NUMBER OF CURRENT MISFIRES WHILE DRIVING UNDER LOAD TO SPECIFY MISFIRING CYLINDER
  • Start the engine.
    NOTE:
    • The fuel injection control enters the deceleration fuel cut zone when the accelerator pedal is fully released while the vehicle is being driven. At this time, the count for the number of misfires is stopped.
  • Verify the number of misfires while the vehicle is being driven for 1 min under the condition of the freeze frame data recorded in Step 3.
  • MF_CAT1
  • MF_CAT_2
  • MF_CAT_3
  • MF_CAT_4
  • MF_EMI1
  • MF_EMI_2
  • MF_EMI_3
    • MF_EMI_4
  • Can a misfire be verified?
Yes Record each of the verified values, then go to the next step.
No Referring to the service questioning results, verify the misfire rate again with the driving mode data added before recording the freeze frame data/snapshot data.
10 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD SPARK PLUGS Yes Go to the troubleshooting procedure to perform the procedure from Step 1.
No Go to the next step.
11 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD IGNITION COIL Yes Go to the troubleshooting procedure to perform the procedure from Step 2.
No Go to the troubleshooting procedure to perform the procedure from Step 3.