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Function Inspection Using M-MDS

DIAGNOSTIC PROCEDURE - 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 2.5T)] .)
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 2.5T)] .)
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 Inspect the suspected sensor and related wiring harness.
  • If there is any malfunction:
    • Repair or replace the malfunctioning part.
      • Go to Troubleshooting Diagnostic 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
  • Start the engine.
  • Verify all accessory loads (A/C, headlights, blower fan, rear window defroster) are off.
  • Under no-load conditions (P or N position), increase the engine speed to 3, 000 rpm and hold for 30 s.
  • Verify the number of misfires.
  • 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 Go to Step 9.
7 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD SPARK PLUGS
  • Switch the spark plugs on a cylinder that is misfiring and a cylinder that is not misfiring. (See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
  • Start the engine.
  • Verify all accessory loads (A/C, headlights, blower fan, rear window defroster) are off.
  • Under no-load conditions (P or N position), increase the engine speed to 3, 000 rpm and hold for 30 s.
  • Verify the number of misfires.
  • MF_CAT1
  • MF_CAT_2
  • MF_CAT_3
  • MF_CAT_4
  • MF_EMI1
  • MF_EMI_2
  • MF_EMI_3
    • MF_EMI_4
  • Is there a change from the recorded number of misfires in Step 6?
 Yes Go to Troubleshooting Diagnostic 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 Troubleshooting Diagnostic Procedure to perform the procedure from Step 2.
No Go to Troubleshooting Diagnostic 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/snap shot data.
10 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD SPARK PLUGS
  • Switch the spark plugs on a cylinder that is misfiring and a cylinder that is not misfiring. (See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
  • 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 9.
  • MF_CAT1
  • MF_CAT_2
  • MF_CAT_3
  • MF_CAT_4
  • MF_EMI1
  • MF_EMI_2
  • MF_EMI_3
    • MF_EMI_4
  • Is there a change from the recorded number of misfires in Step 9?
 Yes Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
No Go to the next step.
11 PURPOSE: VERIFY IF MISFIRE CAUSE IS BAD IGNITION COIL
  • Switch the ignition coils on a cylinder that is misfiring and a cylinder that is not misfiring. (See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
  • 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 9.
  • MF_CAT1
  • MF_CAT_2
  • MF_CAT_3
  • MF_CAT_4
  • MF_EMI1
  • MF_EMI_2
  • MF_EMI_3
    • MF_EMI_4
  • Is there a change from the recorded number of misfires in Step 9?
 Yes Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 2.
No Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 3.
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