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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P0134 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0134 DIAGNOSTIC PROCEDURE TABLE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have 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 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 
NOTE:
  • If fuel monitor DTC, DTC P0132 is retrieved, ignore it until P0134 is fixed.
  • Turn the ignition switch off, then to the ON position. (Engine off)
  • Verify pending and stored DTCs using the WDS or equivalent.
  • Is other DTC present?
 Yes Go to the appropriate DTC troubleshooting procedures.
No Go to the next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is DTC P0134 on FREEZE FRAME DATA?
 Yes Go to the next step.
No Go to troubleshooting procedures for DTC on OBD-II FREEZE FRAME DATA  .
(See DTC TABLE  .)
5 INSPECT INSTALLATION OF FRONT HO2S 
  • Inspect if the front HO2S is loosely installed.
  • Is the sensor installed securely?
 Yes Go to the next step.
No Install sensor securely, then go to Step 10.
6 INSPECT FRONT HO2S HEATER  Yes Go to the next step.
No Replace the front HO2S, then go to Step 10 (See FRONT HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
7 INSPECT FRONT HO2S  Yes Go to the next step.
No Replace the front HO2S, then go to Step 10.
(See FRONT HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
8 INSPECT FRONT HO2S SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY CIRCUIT 
  • Turn the ignition switch to OFF.
  • Disconnect the front HO2S connector.
  • Measure the voltage between front HO2S terminal A (wiring harness-side) and GND.
  • Is the voltage above 3.22 V  ?
 Yes Repair or replace for short to power supply circuit, then go to Step 10.
No Go to the next step.
9 INSPECT FRONT HO2S SIGNAL CIRCUIT FOR OPEN 
  • Disconnect the PCM connector.
  • Inspect for continuity between PCM terminal 2AD (wiring harness-side) and front HO2S terminal A (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace for open circuit, then go to the net step.
10 VERIFY TROUBLESHOOTING OF DTC P0134 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn the ignition switch to the ON position. (Engine off)
  • Clear the DTC from memory using the WDS or equivalent.
  • Perform the KOER self-test (using WDS or equivalent) or the HO2S heater, HO2S, and TWC Repair Verification Drive Mode (not using WDS or equivalent).

    (See KOEO/KOER SELF TEST  .)

    (See OBD-II DRIVE MODE  .)

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