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Home >> Mazda >> 2017 >> 5 GT, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine Control >> Engine Control System Operation Inspection >> EGR Control System Inspection
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EGR Control System Inspection

  1. Crank the engine and verify that EGR valve operation (initial operation) sound is heard.
    • If the operation sound is not heard, connect the M-MDS to the DLC-2 and verify that the DTC P0403:00 is shown. Perform the DTC inspection. (See DTC P0403:00 .)
  2. Start the engine and idle it.
  3. Increase the step value of the EGR valve from 0 to 40 using the SEGRP PID of the simulation function.
  4. Operate the EGR valve and inspect if the engine speed becomes unstable or the engine stalls.
    • If the engine speed does not change, proceed to the following.
    1. Stop the engine.
    2. Remove the EGR valve. (See EGR VALVE REMOVAL/INSTALLATION .)
    3. Connect the EGR valve connector.
    4. Switch the ignition to ON (engine off).
    5. Increase the step value of EGR valve from 0 to 40 using the SEGRP PID.
    6. Verify that the EGR valve operates according to the SEGRP PID.
    • If the EGR valve is operated, clean the EGR valve and reinspect from Step 2.
    • If the EGR valve does not operate, replace the EGR valve and reinspect from Step 2.
  5. Warm up the engine to normal operating temperature.
  6. Access the following PIDs: (See ON-BOARD DIAGNOSTIC TEST .)
    • APP1
    • APP2
    • ECT
    • RPM
    • SEGRP_DSD
    • VSS
  7. Idle the vehicle and verify that the SEGRP value is 0.
    CAUTION:
    • While performing the this step, always operate the vehicle in a safe and lawful manner.
    • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  8. Put the vehicle in drive.
  9. Depress the accelerator pedal and verify that the SEGRP_DSD value is increased.
    • If the EGR valve increases, inspect the following:
    • EGR valve (stuck open or close) (See EGR VALVE INSPECTION .)
    • Wiring harness and connectors (Main relay-EGR valve-PCM)
    • If the SEGRP_DSD value does not increase, inspect the VSS, APP1, APP2, TP REL and ECT PIDs. (See PCM INSPECTION .)
  10. Stop the vehicle and verify that the SEGRP value returns to 0.
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