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Home >> Mazda >> 2010 >> 5 Touring, 2.3 L >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3] >> DTC P0137 >> Diagnostic procedure
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Diagnostic procedure

DTC P0137 [L3] DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) 
  • Is DTC P0137 on FREEZE FRAME DATA (Mode 2)?
 Yes Go to the next step.
No Go to troubleshooting for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE .)
2 VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor, HO2S related) been recorded?
 Yes Go to next step.
No Record FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to next step.
3 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 available repair information.
  • If vehicle is not repaired, go to next step.
No Go to the next step.
4 VERIFY RELATED PENDING OR STORED DTCS 
  • Turn ignition key to OFF, then ON (Engine OFF).
  • Verify pending code or stored DTCs using M-MDS.
  • Is other DTC present?
 Yes Go to appropriate DTC troubleshooting procedures. (See DTC TABLE .)
No Go to the next step.
5 INSPECT HO2S CONNECTOR FOR POOR CONNECTION 
  • Turn ignition key OFF.
  • Disconnect HO2S connector.
  • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion).
  • Is there any malfunction?
 Yes Repair terminal, then go to Step 11.
No Go to the next step.
6 INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND CIRCUIT 
  • Turn the ignition switch off.
  • Inspect continuity between HO2S terminal A (harness-side) and body ground.
  • Is there any voltage reading?
 Yes If the short to ground circuit could be detected:
  • Repair or replace for a possible short to ground.

If the short to ground circuit could not be detected:

Then go to Step 11.
No Go to the next step.
7 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Disconnect PCM connector.
  • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion).
  • Is there any malfunction?
 Yes Repair terminal, then go to Step 11.
No Go to the next step.
8 INSPECT HO2S SIGNAL CIRCUIT FOR OPEN 
  • Inspect continuity between HO2S terminal A (harness-side) and PCM terminal 2Q (harness-side).
  • Is there any continuity?
 Yes Go to the next step.
No Repair or replace harness for open circuit, then go to Step 11.
9 INSPECT HO2S GROUND CIRCUIT FOR OPEN 
  • Inspect continuity between HO2S terminal B (harness-side) and PCM terminal 2AV (harness-side).
  • Is there any continuity?
 Yes Go to the next step.
No Repair or replace harness for open circuit, then go to Step 11.
10 INSPECT HO2S 
 Yes Repair or replace HO2S, then go to the next step.
No Go to the next step.
11 VERIFY TROUBLESHOOTING OF DTC P0137 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn ignition key to ON (Engine OFF).
  • Clear DTC from PCM memory using M-MDS.
  • Perform the KOEO self-test with M-MDS, or "A/F sensor heater, HO2S Heater, A/F sensor, HO2S, and TWC Repair Verification Drive Mode".

    (See KOEO/KOER SELF TEST .)

    (See OBD-II DRIVE MODE .)

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