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Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3 With TC] >> DTC P0137 >> Diagnostic procedure
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Diagnostic procedure

DTC P0137 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 (HO2S related) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME 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 the 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 CODE OR STORED DTC 
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Verify the related PENDING CODE or stored DTCs using the WDS or equivalent.
  • Are other DTCs present?
 Yes Go to appropriate DTC troubleshooting procedure.
(See DTC TABLE ).
No Go to the next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is DTC P0137 on FREEZE FRAME DATA?
 Yes Go to the next step.
No Go to the troubleshooting for the DTC on the FREEZE FRAME DATA.
(See DTC TABLE ).
5 INSPECT REAR HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND AT HARNESS 
  • Turn the ignition switch off.
  • Disconnect rear HO2S and PCM connectors.
  • Verify the continuity between rear HO2S sensor terminal A (wiring harness side) and body ground.
  • Is there continuity?
 Yes Repair for a short to ground circuit, then go to Step 7.
No Go to the next step.
6 INSPECT REAR HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND AT REAR HO2S 
  • Rear HO2S connector disconnected.
  • Verify the continuity between rear HO2S sensor terminal A (part side) and body ground.
  • Is there continuity?
 Yes Replace the rear HO2S then go to the next step.
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0137 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Perform the HO2S heater, HO2S and TWC Repair Verification Drive Mode.

    (See OBD-II DRIVE MODE ).

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