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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 P2237 >> Diagnostic procedure
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Diagnostic procedure

DTC P2237 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 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is DTC P2237 on FREEZE FRAME DATA?
 Yes Go to the next step.
No Go to troubleshooting for DTC on FREEZE FRAME DATA.
(See DTC TABLE ).
4 INSPECT FRONT HO2S CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch to off.
  • Disconnect the front HO2S connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to Step.
No Go to the next step.
5 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch to off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to Step.
No Go to the next step.
6 INSPECT FRONT HO2S POSITIVE CURRENT CIRCUIT FOR OPEN AT PCM - FRONT HO2S 
  • Front HO2S and PCM connectors disconnected.
  • Verify the continuity between PCM terminal 2D and front HO2S terminal 1A.
  • Is there continuity?
 Yes Replace the front HO2S, then go to the next step.
No Repair or replace the wiring harness for an open, then go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P2237 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 same DTC present?
 Yes Replace the 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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