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Diagnostic procedure

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DIAGNOSTIC PROCEDURE CHART

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (catalyst related) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 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 VERIFY RELATED PENDING AND STORED DTC 
  • Switch the ignition to off, then to ON (engine off).
  • Verify pending and stored DTCs using the M-MDS.

    (See ON-BOARD DIAGNOSTIC TEST .)

  • Are any other DTCs present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No Go to the next step.
4 INSPECT FOR LEAKAGE FROM EXHAUST SYSTEM 
  • Visually inspect the exhaust gas system.
  • Is there any leakage?
 Yes Repair or replace the malfunctioning part according to the inspection results, then go to Step 8.
No Go to the next step.
5 INSPECT INSTALLATION OF A/F SENSOR 
  • Inspect the A/F sensor for looseness.
  • Is there any malfunction?
 Yes Retighten the A/F sensor, then go to Step 8.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
6 INSPECT INSTALLATION OF HO2S 
  • Inspect the HO2S for looseness.
  • Is there any malfunction?
 Yes Retighten the HO2S, then go to Step 8.
(See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
No Go to the next step.
7 INSPECT TWC 
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE .)

  • Switch the ignition to off, then to ON.
  • Inspect the TWC.
  • Is there any malfunction?
 Yes Replace the TWC, then go to the next step.
(See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
No Go to the next step.
8 VERIFY DTC TROUBLESHOOTING COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE .)

  • Perform the Drive Mode 03 (EGR System, A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode).

    (See OBD-II DRIVE MODE .)

  • Is the PENDING CODE for this DTC present?
 Yes Repeat the inspection from Step 1.
  • If the malfunction recurs, replace the PCM.

(See PCM REMOVAL/INSTALLATION .)
Go to the next step.
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
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