2012 Lexus IS 250C Automatic TransFACTORY OEM SERVICE PROCEDURE

Air Fuel Ratio Sensor: Removal: Removal

  1. PRECAUTION (w/ Navigation System for HDD) 
    NOTE:

    After the engine switch is turned off, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the engine switch off, make sure to wait at least 60 seconds before disconnecting the cable from the negative (-) battery terminal.

  2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
  3. REMOVE COOL AIR INTAKE DUCT SEAL  . Refer to REMOVAL - Step 1
  4. REMOVE ENGINE ROOM SIDE COVER LH  . Refer to REMOVAL - Step 2
  5. REMOVE ENGINE ROOM SIDE COVER  . Refer to REMOVAL - Step 3
  6. REMOVE V-BANK COVER SUB-ASSEMBLY  . Refer to REMOVAL - Step 4
  7. REMOVE ENGINE UNDER COVER 
  8. REMOVE FRONT FLOOR COVER LH  . Refer to REMOVAL - Step 21
  9. REMOVE FRONT FLOOR COVER RH  . Refer to REMOVAL - Step 22
  10. REMOVE NO. 2 FLOOR UNDER COVER  . Refer to REMOVAL - Step 23
  11. REMOVE NO. 1 FLOOR UNDER COVER  . Refer to REMOVAL - Step 24
  12. REMOVE NO. 1 BODY MOUNTING BRACKET SUB-ASSEMBLY LH  . Refer to REMOVAL - Step 25
  13. REMOVE NO. 1 BODY MOUNTING BRACKET SUB-ASSEMBLY RH  . Refer to REMOVAL - Step 26
  14. REMOVE NO. 2 ENGINE UNDER COVER 
  15. REMOVE REAR BODY SUPPORT BRACKET  . Refer to REMOVAL - Step 9
  16. REMOVE FRONT CENTER FLOOR BRACE  . Refer to REMOVAL - Step 10
  17. REMOVE FRONT EXHAUST PIPE ASSEMBLY  . Refer to REMOVAL - Step 7
  18. REMOVE NO. 1 EXHAUST PIPE SUPPORT BRACKET SUB-ASSEMBLY (for Automatic Transmission)  . Refer to REMOVAL - Step 12
  19. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE  See step  7
  20. REMOVE POWER STEERING ECU ASSEMBLY 
    1. Remove the power steering ECU assembly. Refer to REMOVAL .
  21. REMOVE BATTERY TRAY 
    1. Remove the 3 bolts and battery tray.
      Fig 1: Identifying Battery Tray
      GTY284575Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  22. REMOVE NO. 4 ENGINE WIRE 
    1. Remove the engine room No. 1 relay block cover.
    2. Remove the nut and separate the wire from the engine room No. 1 junction block.
      Fig 2: Identifying No. 4 Engine Wire
      GTY271797Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the connector and remove the 2 clamps.
  23. REMOVE AIR FUEL RATIO SENSOR (for Bank 1 Sensor 1) 
    1. Disconnect the 2 clamps and air fuel ratio sensor connector (for Bank 1 Sensor 1).
      Fig 3: Location of Air Fuel Ratio Sensor (For Bank 1 Sensor 1)
      GTY358315Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using SST, remove the air fuel ratio sensor (for Bank 1 Sensor 1) from the exhaust manifold RH.
      Fig 4: Air Fuel Ratio Sensor (For Bank 1 Sensor 1)
      GTY355579Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • SST: 09224-00010 
  24. SEPARATE NO. 3 ENGINE ROOM RELAY BLOCK ASSEMBLY  . Refer to REMOVAL - Step 23
  25. REMOVE EXHAUST MANIFOLD SUB-ASSEMBLY LH  . Refer to REMOVAL - Step 24
  26. REMOVE AIR FUEL RATIO SENSOR (BANK 2 SENSOR 1) 
    1. Using SST, remove the air fuel ratio sensor (for Bank 2 Sensor 1) from the exhaust manifold LH.
      Fig 5: View Of Removing Air Fuel Ratio Sensor From Exhaust Manifold LH Using SST
      GTY145864Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • SST: 09224-00010 
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.