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On-Vehicle Inspection

  1. INSPECT DRIVE BELT 
    1. Visually check the belt for excessive wear, frayed cords, etc.

      If any defect is found, replace the drive belt.

      HINT:

      Cracks on the rib side of a belt are considered acceptable. If the missing chunks from the ribs are found on the belt, it should be replaced.

    Fig 1: Identifying Drive Belt
    G00919071Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. BLEED POWER STEERING SYSTEM 
    1. Check the fluid level.
    2. Jack up the front of the vehicle and support it with the stands.
    3. Turn the steering wheel.
      1. With the engine stopped, turn the wheel slowly from lock to lock several times.
    4. Lower the vehicle.
    5. Start the engine.
      1. Run the engine at idle for a few minutes.
    6. Turn the steering wheel.
      1. With the engine idling, turn the wheel to left or right full lock position and keep it there for 2 - 3 seconds, then turn the wheel to the opposite full lock position and keep it there for 2 - 3 seconds.
      2. Repeat (1) several times.
    7. Stop the engine.
    8. Check for forming or emulsification.

      Especially, if the system has to be bled twice because of foaming or emulsification, check for fluid leaks in the system.

    9. Check the fluid level.
      Fig 2: Checking Fluid Level
      G00919072Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK FLUID LEVEL 
    1. Keep the vehicle level.
    2. With the engine stopped, check the fluid level in the oil reservoir.

      If necessary, add fluid.

      1. Fluid: ATF DEXRON® II or III 

      HINT:

      Check that the fluid level is within the HOT LEVEL range on the reservoir. If the fluid is cold, check that it is within the COLD LEVEL range.

    3. Start the engine and run it at idle.
    4. Turn the steering wheel from lock to lock several times to raise fluid temperature.
      1. Fluid temperature: 75 - 80°C (167 - 176°F) 
      Fig 3: Measuring Fluid Level
      G00919073Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Check for foaming or emulsification.

      If foaming or emulsification is identified, bleed the power steering system.

      Fig 4: Checking Foaming Or Emulsification
      G00919074Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. With the engine idling, measure the fluid level in the oil reservoir.
    7. Stop the engine.
    8. Wait a few minutes and remeasure the fluid level in the oil reservoir.
      Fig 5: Measuring Fluid Level In Oil Reservoir
      G00919075Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Maximum fluid level rise: 5 mm (0.20 in.) 

      If a problem is found, bleed the power steering system.

    9. Check the fluid level.
  4. CHECK STEERING FLUID PRESSURE 
    1. Disconnect the pressure feed tube assy from the vane pump assy ( OVERHAUL ).
    2. Connect SST, as shown in the illustration.
      1. SST 09640-10010 (09641-01010, 09641-01030, 09641-01060)
      NOTE: Check that the valve of the SST is in the open position.
    3. Bleed the power steering system.
    4. Start the engine and run it at idle.
    5. Turn the steering wheel from lock to lock several times to raise fluid temperature.
      1. Fluid temperature: 75 - 80 °C (167 - 176 °F) 
      Fig 6: Measuring Steering Fluid Pressure
      G00919076Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. With the engine idling, close the valve of the SST and observe the reading on the SST.
      1. Minimum fluid pressure: 8,336 kPa (85 kgf/cm 2  , 1,209 psi) 
      NOTE:
      • Do not keep the valve closed for more than 10 seconds.
      • Do not let the fluid temperature become too high.
      Fig 7: Identifying Closed Position Of Valve
      G00919077Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. With the engine idling, open the valve fully.
    8. Measure the fluid pressure at engine speeds of 1,000 RPM and 3,000 RPM.
      1. Difference fluid pressure: 490 kPa (5 kgf/cm 2  , 71 psi) or less 
      NOTE: Do not turn the steering wheel.
      Fig 8: Identifying Open Position Of Valve And Unlock Steering
      G00919078Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. With the engine idling and valve fully opened, turn the steering wheel to full lock position.
      Fig 9: Identifying Open Position Of Valve And Lock Steering
      G00919079Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Minimum fluid pressure: 8,336 kPa (85 kgf/cm 2  , 1,209 psi) 
      NOTE:
      • Do not maintain lock position for more than 10 seconds.
      • Do not let the fluid temperature become too high.
    10. Disconnect the SST.
      1. SST 09640-10010 (09641-01010, 09641-01030, 09641-01060)
    11. Connect the pressure feed tube assy to the vane pump assy ( OVERHAUL ).
    12. Bleed the power steering system.
  5. CHECK STEERING EFFORT 
    1. Center the steering wheel.
    2. Remove the steering wheel pad (See OVERHAUL ).
    3. Start the engine and run it at idle.
    4. Measure the steering effort in both directions.
      1. Steering effort (Reference): 6 N.m (60 kgf.cm, 53 in. lbf) or less 

      HINT:

      Take the tire type, pressure and contact surface into consideration before making your diagnosis.

    5. Torque the steering wheel set nut.
      1. Torque: 50 N.m (510 kgf.cm, 37 ft.lbf) 
    6. Install the steering wheel pad (See OVERHAUL ).
    Fig 10: Checking Steering Effort
    G00919080Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002