LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2002 >> ES 300 >> Repair and Diagnosis >> Steering >> Power Steering >> Steering Control System >> Power Steering System >> On-Vehicle Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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.

      NOTE: 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.
  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 step  1 several times.
    7. Stop the engine.
      Fig 1: Inspecting Drive Belt
      G01208899Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 power steering fluid level.
      Fig 2: Checking For Emulsification
      G01208900Courtesy 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.

      Fluid:  ATF DEXRON® II or III

      NOTE: Check that the fluid level is within the HOT LEVEL range on the reservoir cap. If the fluid is cold, check that it is within the COLD LEVEL range.
      Fig 3: Checking Fluid Level
      G01208901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Start the engine and run it at idle.
    4. Turn the steering wheel from lock to lock several times to raise fluid temperature.

      Fluid Temperature:  75-80°C (167-176°F)

    5. Check for foaming or emulsification.

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

      Fig 4: Checking For Emulsification
      G01208902Courtesy 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.

      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 from the power steering gear. See RACK & PINION POWER STEERING GEAR ASSEMBLY .
    2. Connect SST, as shown in the illustration.

      SST 09640-10010 (09641-01010, 09641-01020, 09641-01030)

      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.

      Fluid Temperature: 75-80°C (167-176°F) 

      Fig 5: Measuring Fluid Level
      G01208903Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 6: Checking valve Of SST
      G01208904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. With the engine idling, close the valve of the SST and observe the reading on the SST.

      Fluid Pressure:  7800-8300 kPa (80-85 kgf/cm2 , 1138-1209 psi

      NOTE:
      • Do not keep the valve closed for more than 10 seconds.
      • Do not let the fluid temperature become too high.
      Fig 7: Observing SST Reading With Closed Valve
      G01208905Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. With the engine idling, open the valve fully.
    8. Measure the fluid pressure at engine speeds of 1000 RPM and 3000 RPM.

      Fluid Pressure Difference:  490 kPa (5 kgf/cm2 , 71 psi) or less.

      NOTE: Do not turn the steering wheel.
      Fig 8: Observing SST Reading With Open Valve
      G01208906Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. With the engine idling and valve fully opened, turn the steering wheel to full lock position.

      Fluid Pressure:  7800-8300 kPa (80-85 kgf/cm2 , 1138-1209 psi)

      NOTE:
      • Do not maintain lock position for more than 10 seconds.
      • Do not let the fluid temperature become too high.
      Fig 9: Observing SST Reading With Fully Open Valve
      G01208907Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    10. Disconnect the SST.

      SST 09640-10010 (09641-01010, 09641-01020, 09641-01030)

    11. Connect the pressure feed tube to the power steering gear. See RACK & PINION POWER STEERING GEAR ASSEMBLY .
    12. Bleed the power steering system.
      Fig 10: Checking Steering Effort
      G01208908Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Check steering effort
    1. Center the steering wheel assembly.
    2. Remove the horn button assembly. See OVERHAUL .
    3. Start the engine and run it at idle.
    4. Measure the steering effort in both directions.

      Steering Effort (Reference):  6 N.m (60 kgf.cm, 53 in.lbf) or less

      NOTE: Take the tire type, pressure and contact surface into consideration before making your diagnosis.
    5. Install the steering wheel assembly set nut.

      Torque:  50 N.m (510 kgf.cm, 37 ft.lbf)

    6. Install the horn button assembly. See OVERHAUL .
scientia non olet · About LEMON Manuals