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Home >> Mazda >> 2017 >> 5 GT, Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control (1 Of 3) >> DTC P0134-00: A/F Sensor Circuit No Activity Detected >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0134:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2)
  • Perform the Freeze Frame PID Data Access Procedure. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the DTC P0134:00 on FREEZE FRAME DATA (Mode 2)?
 Yes Go to the next step.
No Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE .)
2 VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED
  • Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor, HO2S related) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the 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 the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
4 VERIFY RELATED PENDING CODE AND/OR DTC
NOTE:
  • If the fuel monitor, DTC P0132:00 is retrieved, ignore it until DTC

    P0134:00 is fixed.

  • Switch the ignition to off, then to ON (engine off).
  • Perform the Pending Trouble Code Access Procedure and DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the PENDING CODE/DTC P2237:00, P2243:00 or P2251:00 also present?
 Yes Go to the applicable PENDING CODE or DTC inspection.
(See DTC P2237-00: .)
(See DTC P2243-00: .)
(See DTC P2251-00: .)
No Go to the next step.
5 INSPECT INSTALLATION OF A/F SENSOR
  • Inspect installation of A/F sensor.
  • Is the A/F sensor installed securely?
 Yes Go to the next step.
No Retighten the A/F sensor, then go to Step 15.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)
6 INSPECT EXHAUST SYSTEM FOR GAS LEAKAGE
  • Visually inspect for exhaust gas leakage between exhaust manifold and A/F sensor.
  • Is there any leakage?
 Yes Repair or replace the malfunctioning part according to the inspection results, then go to Step 15.
No Go to the next step.
7 INSPECT A/F SENSOR CONNECTOR CONDITION
  • Switch the ignition to off.
  • Disconnect the A/F sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 15.
No Go to the next step.
8 INSPECT A/F SENSOR HEATER
 Yes Replace the A/F sensor, then go to Step 15.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
9 INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND
  • Verify that the A/F sensor connector is disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • A/F sensor terminal 1C
    • A/F sensor terminal 1B
    • A/F sensor terminal 1A
    • A/F sensor terminal 2D
  • Is there continuity?
 Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

    If the short to ground circuit could not be detected:

  • Replace the PCM (short to ground in the PCM internal circuit). (See PCM REMOVAL/INSTALLATION .)

Go to Step 15.
No Go to the next step.
10 INSPECT PCM CONNECTOR CONDITION
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 15.
No Go to the next step.
11 INSPECT A/F SENSOR CIRCUIT FOR OPEN CIRCUIT
  • Verify that the A/F sensor and PCM connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • A/F sensor terminal 1C-PCM terminal 2Z
    • A/F sensor terminal 1B-PCM terminal 2AC
    • A/F sensor terminal 1A-PCM terminal 2AD
    • A/F sensor terminal 2D-PCM terminal 2A
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 15.
12 INSPECT ENGINE COMPRESSION
 Yes Repair or replace the malfunctioning part according to the inspection results, then go to Step 15.
No Go to the next step.
13 INSPECT SEALING OF ENGINE COOLANT PASSAGE
  • Perform the "ENGINE COOLANT LEAKAGE INSPECTION". (See ENGINE COOLANT LEAKAGE INSPECTION .)
  • Does the radiator cap tester needle drop even though there is no engine coolant leakage from the radiator or the hoses?
 Yes Engine coolant leakage from the engine (between the combustion chamber and the engine coolant passage) may have occurred.
  • Verify the conditions of the gasket and the cylinder head.
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results, then go to Step 15.
No Go to the next step.
14 INSPECT A/F SENSOR
 Yes Replace the A/F sensor, then go to the next step.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
15 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE .)
  • Perform the Drive Mode 03 (EGR System, A/F Sensor Heater, HO2S Heater, A/F Sensor, HO2S and TWC Repair Verification Drive Mode). (See OBD-II DRIVE MODE .)
  • Is the PENDING CODE for this DTC present?
 Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
16 VERIFY AFTER REPAIR PROCEDURE
 Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
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