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Function Inspection Using M-MDS

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P0300-00: (PCM - VIN Y) FUNCTION INSPECTION USING M-MDS

Step Inspection Results Action
1 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 (VIN Y)] .)
2 PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION 
  • Record the freeze frame data/snapshot data and diagnostic monitoring test results (misfire related).
    NOTE:
    • Recording can be facilitated using the screen capture function of the PC.
 - Go to the next step.
3 PURPOSE: INSPECT FOR OTHER RELATED DTCs 
  • Perform the DTC inspection for the PCM. (See DTC INSPECTION .)
  • Are any other DTCs displayed?
 Yes Repair or replace the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (VIN Y)] .)
No Go to the next step.
4 PURPOSE: VERIFY IF THERE IS PID ITEM CAUSING DRASTIC CHANGES OF ACCELERATION FLUCTUATION BY INPUT SIGNAL TO PCM 
  • Start the engine.
  • Access the following PCM PIDs using the MMDS.
    • APP1
    • APP2
    • BOOST_AIR_TEMP_VOLT
    • BOOST_AIR_TEMP
    • ECT
    • ECT_VOLT
    • IAT
    • MAF
    • MAP_VOLT
    • ENG_RPM
    • TP1
    • TP2
    • VSS
  • Is there a PID item affected by acceleration fluctuation?
 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 repair completion verification 1.
  • If there is no malfunction:
    • Go to the next step.
No Go to the next step.
5 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 defogger) 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.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • Can a misfire be verified?
 Yes Record each of the verified values, then go to the next step.
No Go to Step 8.
6 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. (Refer to SPARK PLUG REMOVAL/INSTALLATION (VIN Y) in the service information.)
  • Start the engine.
  • Verify all accessory loads (A/C, headlights, blower fan, rear window defogger) 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.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • Is there a change from the recorded number of misfires in Step 5?
 Yes Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
No Go to the next step.
7 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. (Refer to IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION (VIN Y) in the service information.)
  • Start the engine.
  • Verify all accessory loads (A/C, headlights, blower fan, rear window defogger) 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.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • Is there a change from the recorded number of misfires in Step 5?
 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.
8 PURPOSE: RECORD NUMBER OF CURRENT MISFIRES DURING NO 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 2.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • 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.
9 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. (Refer to SPARK PLUG REMOVAL/INSTALLATION (VIN Y) in the service information.)
  • 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 driving conditions in which misfires were verified in Step 8.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • Is there a change from the recorded number of misfires in Step 8?
 Yes Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
No Go to the next step.
10 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. (Refer to IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION (VIN Y) IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION in the service information.)
  • 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 driving conditions in which misfires were verified in Step 8.
    • Access the following PCM PIDs using the M-MDS. (See PID/DATA MONITOR TABLE [PCM (VIN Y)] .)
      • MISFIRE_CYL1_CAT
      • MISFIRE_CYL2_CAT
      • MISFIRE_CYL3_CAT
      • MISFIRE_CYL4_CAT
      • MISFIRE_CYL1_EMI
      • MISFIRE_CYL2_EMI
      • MISFIRE_CYL3_EMI
      • MISFIRE_CYL4_EMI
  • Is there a change from the recorded number of misfires in Step 8?
 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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