Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0134 [L3] DIAGNOSTIC PROCEDURE

STEP

INSPECTION

ACTION

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.

Record the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.

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.

Go to the next step.

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.

Go to the next step.

IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA

Is DTC P0134 on FREEZE FRAME DATA?

Yes

Go to the next step.

Go to troubleshooting procedures for DTC on FREEZE FRAME DATA.
(See DTC TABLE .)

VERIFY CURRENT INPUT SIGNAL STATUS

Warm up engine.
Access O2S11 PID using the WDS or equivalent.
Verify PID while racing engine in PARK (ATX) or NEUTRAL (MTX).
Is PID normal?
- More than 0.55 V when suddenly depressing accelerator pedal (rich condition)
- Less than 0.55 V just after releasing the of accelerator pedal (lean condition)

Yes

Go to step 8.

Go to the next step.

INSPECT INSTALLATION OF FRONT HO2S

Inspect if the front HO2S is loosely installed.
Is the sensor installed securely?

Yes

Go to the next step.

Install sensor securely, then go to Step 10.

INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM

Visually inspect if the re is any gas leakage between the exhaust manifold and front HO2S.
Is there gas leakage?

Yes

Repair or replace any malfunctioning exhaust part, then go to Step 10.

Inspect the following harnesses for open circuit or short to ground, repair or replace wiring harness if necessary.
- Front HO2S terminal A (wiring harness-side) to PCM terminal 1AB (wiring harness-side)
If all items above are normal, replace malfunctioning sensor.

Then go to Step 10.

INSPECT SEALING OF ENGINE COOLANT PASSAGE

Perform the ENGINE COOLANT LEAKAGE INSPECTION.
(See ENGINE COOLANT LEAKAGE INSPECTION .)
Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to inspection results, then go to Step 10.

Go to the next step.

INSPECT ENGINE COMPRESSION

Inspect engine compression.
(See COMPRESSION INSPECTION .)
Is it normal?

Yes

Go to the next step.

Perform engine overhaul for repairs, then go to the next step.

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 PCM Adaptive Memory Produce Drive Mode and 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 the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)

Go to the next step.

VERIFY AFTER REPAIR PROCEDURE

Perform the "AFTER REPAIR PROCEDURE".
(See AFTER REPAIR PROCEDURE .)
Are any DTC present?

Yes

Go to the applicable DTC troubleshooting.
(See DTC TABLE .)

Troubleshooting completed.

⁽¹⁾	California emission regulation applicable model

⁽²⁾	Except for California emission regulation applicable model