Inspection Procedure

HINT:

Hand-held tester only:

Narrowing down the trouble area is possible by performing "A/F CONTROL" ACTIVE TEST (heated oxygen sensor or other trouble areas can be distinguished).

1. Perform ACTIVE TEST using hand-held tester (A/F CONTROL).

HINT:

"A/F CONTROL" is the ACTIVE TEST which changes the injection volume to -12.5 % or +25 %.

1. Connect the hand-held tester to the DLC3 on the vehicle.
2. Turn the ignition switch ON.
3. Warm up the engine by running the engine speed at 2,500 rpm for approximately 90 seconds.
4. Select the item "DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL".
5. Perform "A/F CONTROL" with the engine in an idle condition (press the right or left button).

   Result: 

   Heated oxygen sensor reacts in accordance with increase and decrease of injection volume +25 % --> rich output: More than 0.5 V, -12.5 % --> lean output: Less than 0.4 V 

   NOTE: There is a delay of few seconds in the sensor 1 (front sensor) output, and there is about 20 seconds delay at maximum in the sensor 2 (rear sensor).
   Fig 1: Heated Oxygen Sensor Injection Volume And Output Voltage Specifications

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   The following of A/F CONTROL procedure enables the technician to check and graph the voltage outputs of both the heated oxygen sensors.

   For displaying the graph indication, enter "ACTIVE TEST / A/F CONTROL / USER DATA", then select "O2S B1S1 and O2S B1S2" by pressing "YES" button and push "ENTER" button before pressing "F4" button.

   HINT:

   • If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may be open.
   • Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
   • A high heated oxygen sensor (sensor 1) voltage (0.5 V or more) could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.
   • A low heated oxygen sensor (sensor 1) voltage (0.4 V or less) could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0134) 
   1. Connect the hand-held tester or the OBD II scan tool to the DLC3.
   2. Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
   3. Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES".
   4. Read the DTCs.

      Result: 

      RESULT REFERENCE
      
      

      Display (DTC output)	Proceed to
      P0134	A
      P0134 and other DTCs	B

   HINT:

   If any other codes besides P0134 are output, perform the troubleshooting for those DTCs first.

   • B : GO TO RELEVANT  DIAGNOSTIC TROUBLE CODE CHART  
   • A; go to next step 
2. READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (OUTPUT VOLTAGE OF HEATED OXYGEN SENSOR) 
   1. Connect the hand-held tester or the OBD II scan tool to the DLC3.
   2. Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
   3. Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / O2S B1S1".
   4. Warm up the engine to the normal operating temperature above 75°C (169°F).
   5. Read the output voltage of the heated oxygen sensor when the engine speed is suddenly increased.

   HINT:

   Quickly accelerate the engine to 4,000 rpm 3 times by using the accelerator pedal.

   Standard: 

   Heated oxygen sensor outputs a RICH signal (0.45 V or more) at least once. 

   • OK : Go to step   12 
   • NG : GO to next step 
3. CHECK CONNECTION OF PCV HOSE 
   • NG : REPAIR OR REPLACE PCV HOSE 
   • OK : Go to next step 
4. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE) 
   1. Disconnect the H5 heated oxygen sensor connector.
   2. Measure the resistance between the terminals of the heated oxygen sensor connector.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      HT (H5-1) - +B (H5-2)	5 to 10 Ω at 20°C (68°F)
      HT (H5-1) - E1 (H5-4)	10 kΩ or higher

   3. Reconnect the heated oxygen sensor connector.
   Fig 2: Identifying Heated Oxygen Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • NG : REPLACE HEATED OXYGEN SENSOR 
   • OK : Go to next step 
5. INSPECT EFI RELAY 
   1. Remove the EFI relay from the engine room R/B.
   2. Check for continuity in the EFI relay.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      1 - 2	Continuity
      3 - 5	No continuity
      	Continuity (Apply battery voltage to terminals 1 and 2)

   3. Install the EFI relay.
   • NG : REPLACE EFI RELAY 
     Fig 3: Inspecting EFI Relay

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • OK : Go to next step 
6. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM) 
   1. Disconnect the H5 heated oxygen sensor connector.
   2. Disconnect the E4 ECM connector.
   3. Check the resistance between the wire harness side connectors.

      Standard (Check for open): 

      TESTER CONNECTION AND SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      HT (H5-1) - HT1A (E4-4)	Below 1 Ω
      OX (H5-3) - OX1A (E4-23)

      Standard (Check for short): 

      TESTER CONNECTION AND SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      HT (H5-1) or HT1A (E4-4) - Body ground	10 kΩ or higher
      OX (H5-3) or- OX1A (E4-23) - Body ground

   4. Reconnect the ECM connector.
   5. Reconnect the heated oxygen sensor connector.
   Fig 4: Identifying H5 Heated Oxygen Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 5: Installing E4 ECM Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 6: Bank 1 Sensor 1 System Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 
   • OK : Go to next step 
7. CHECK WHETHER MISFIRE IS OCCURRED OR NOT BY MONITORING DTC AND DATA LIST 
   • NG : PERFORM TROUBLESHOOTING FOR MISFIRE (See  DTC P0300 RANDOM/MULTIPLE CYLINDER MISFIRE DETECTED, DTC P0301 CYLINDER 1 MISFIRE DETECTED, DTC P0302 CYLINDER 2 MISFIRE DETECTED, DTC P0303 CYLINDER 3 MISFIRE DETECTED, DTC P0304 CYLINDER 4 MISFIRE DETECTED  ) 
   • OK : Go to next step 
8. CHECK AIR INDUCTION SYSTEM 
   1. Check the air induction system for vacuum leaks.
   • NG : REPAIR OR REPLACE AIR INDUCTION SYSTEM 
   • OK : Go to next step 
9. CHECK FUEL PRESSURE (See  ON-VEHICLE INSPECTION  ) 
   1. Check the fuel pressure (high or low pressure).
   • NG : REPAIR OR REPLACE FUEL SYSTEM 
   • OK : Go to next step 
10. INSPECT FUEL INJECTOR ASSY (INJECTION AND VOLUME) (See  INSPECTION  ) 
    • NG : REPLACE FUEL INJECTOR ASSY 
    • OK : Go to next step 
11. CHECK FOR EXHAUST GAS LEAKS 
    • NG : REPAIR OR REPLACE EXHAUST GAS LEAKAGE POINT 
    • OK : REPLACE HEATED OXYGEN SENSOR 
12. PERFORM  CONFIRMATION DRIVING PATTERN  

    HINT:

    Clear all DTCs prior to performing the confirmation pattern.

    • GO to next step 
13. READ OUTPUT DTC (DTC P0134 IS OUTPUT AGAIN) 
    1. Connect the hand-held tester or the OBD II scan tool to the DLC3.
    2. Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
    3. Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES".
    4. Read the DTCs.

       Result: 

       RESULT REFERENCE
       
       

       Display (DTC output)	Proceed to
       No output	A
       P0134	B

    • B : REPLACE ECM (See  REPLACEMENT  ) 
    • A; go to next step 
14. CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST 
    • NO : CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS  ) 
    • YES : DTC IS CAUSED BY RUNNING OUT OF FUEL