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Diagnostic Procedure

DTC P0133 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 
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Verify the pending or stored DTCs using the WDS or equivalent.
  • Is DTC P0443 also present?
Yes Go to DTC P0443 troubleshooting procedures, then go to Step 13.
No Go to the next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is DTC P0133 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 VERIFY CURRENT INPUT SIGNAL STATUS 
  • Warm up the engine.
  • Access O2S11 PID using the WDS or equivalent.
  • Inspect PID under following accelerator pedal conditions in PARK (AT) or NEUTRAL (MT).
  • Is PID normal?
    • Loss than 1 mA  when suddenly depressing accelerator pedal (rich condition).
    • More than 1 mA  just after release of accelerator pedal (lean condition).
Yes Go to Step 8.
No Go to the next step.
6 INSPECT INSTALLATION OF FRONT HO2S 
  • Inspect if the front HO2S is loosely installed.
  • Is the front HO2S installed securely?
Yes Go to the next step.
No Retighten the front HO2S, then go to Step 13.
7 INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM 
  • Visually inspect if there is any gas leakage is found between the exhaust manifold and front HO2S.
  • Is there gas leakage?
Yes Repair or replace the malfunctioning exhaust part, then go to Step 13.
(See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
No Replace sensor, then go to Step 13.
8 INSPECT LONG TERM FUEL TRIM 
  • Access the LONGFT1 PID.
  • Compare it with FREEZE FRAME DATA recorded at Step 1.
  • Is it below FFD value?
Yes The engine is driven under rich condition. Go to the next step.
No The engine is driven under lean condition. Go to Step 10.
9 INSPECT FUEL LINE PRESSURE (EXCESSIVE FUEL LINE PRESSURE) 
  • Turn the ignition switch off.
  • Inspect the fuel line pressure while the engine running.

    (See FUEL LINE PRESSURE INSPECTION .)

  • Is the fuel line pressure normal?
Yes Go to Step 12.
No Inspect the fuel pump maximum pressure, and fuel return pipe for clogging.
(See FUEL PUMP UNIT INSPECTION .) Then go to Step 13.
10 INSPECT FUEL LINE PRESSURE (LOW FUEL LINE PRESSURE) 
  • Turn the ignition switch off.
  • Inspect the fuel line pressure while the engine running.

    (See FUEL LINE PRESSURE INSPECTION .)

  • Is the fuel line pressure normal?
Yes Go to Step 12.
No Go to the next step.
11 INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DELIVERY PIPE 
  • Visually inspect the fuel line for any leakage.
  • Is there fuel leakage?
Yes Replace the fuel line, then go to Step 13.
No Inspect the fuel filters for the following:
  • Foreign material or stain inside the fuel filter (low-pressure side)
Perform the following actions according to the result.
  • If foreign material or stain is found inside the fuel filter (low-pressure side), clean the fuel tank and fuel filter.
  • If normal, replace the fuel pump unit.

    (See FUEL PUMP UNIT REMOVAL/INSTALLATION .)


Then go to Step 13.
12 INSPECT SEALING OF ENGINE COOLANT PASSAGE  Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results. Then go to the next step.
13 VERIFY TROUBLESHOOTING OF DTC P0133 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn the ignition switch to the ON position. (Engine off)
  • Clear the DTC from the 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 for this DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
14 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC troubleshooting.
(See DTC TABLE  .)
No Troubleshooting completed.