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Diagnostic procedure

DTC P0446 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (EVAP system related) been recorded?
Yes Go to the next step.
No Record FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Check for related Service Bulletins and/or online repair information availability.
  • Is any related repair information available?
Yes Perform the repair or diagnostic according to the available repair information.
  • If the vehicle is not repaired, then go to the next step.
No Go to the next step.
3 CHECK COV CONTROL (EVAP SYSTEM LEAK DETECTION PUMP CIRCUIT FOR SHORT TO POWER) 
  • Turn ignition switch to the ON position (engine OFF).
  • Disconnect the EVAP system leak detection pump connector.
  • Measure the voltage between EVAP system leak detection pump connector terminal C (wiring harness-side) and body ground.
  • Is the voltage B+  ?
Yes Repair or replace the wiring harness, then go to Step 5.
No Go to the next step.
4 INSPECT COV (EVAP SYSTEM LEAK DETECTION PUMP) 
Yes Go to the next step.
No Replace the EVAP system leak detection pump, then go to the next step.
5 VERIFY TROUBLESHOOTING OF DTC P0446 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn the ignition switch to the ON position (Engine off).
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Perform the EVAP system test using the WDS or equivalent.

    (See EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK INSPECTION ).

  • Is the same DTC present?
    NOTE:
    • If the EVAP system test function is not available, preform the following procedure:
      • Perform "EVAP System Repair Verification Drive Mode".

        (See OBD-II DRIVE MODE )

      • Is the PENDING CODE for this DTC present?
Yes Replace the PCM, then go to the next step.
No Go to the next step.
6 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No Troubleshooting completed.