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Hydraulic Test

  1. PERFORM HYDRAULIC TEST 
    1. Measure the line pressure.
      NOTE:
      • Perform the test at the normal operation fluid temperature the 50 to 80°C (122 to 176°F).
      • The line pressure test should always be carried out in pairs. One technician should observe the conditions of wheels or wheel stoppers outside the vehicle while the other is performing the test.
      • Be careful to prevent SST hose from interfering with the exhaust pipe.
      • This check must be conducted after checking and adjusting engine.
        Fig 1: Measuring Line Pressure With SST
        G04105477Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Perform under condition that A/C is OFF.
      • When conducting stall test, do not continue more than 5 seconds.
      1. Warm up the ATF (Automatic Transmission Fluid).
      2. Remove the test plug on the transmission case center right side and connect SST.

        SST 09992-00095 (09992-00231, 09992-00271)

      3. Fully apply the parking brake and chock the 4 wheels.
      4. Start the engine and check idling speed.
      5. Keep your left foot pressing firmly on the brake pedal and shift into D position.
      6. Measure the line pressure when the engine is idling.
      7. Depress the accelerator pedal all the way down.

        Quickly read the highest line pressure when engine speed reaches stall speed.

      8. In the same manner, do the test in R position.
    2. Perform steps  a to  g with the shift lever on R.

      Specified line pressure: 

      SPECIFIED LINE PRESSURE

      Condition Shift Lever on D Shift Lever on R
      Idling 355 to 425 kPa (3.6 to 4.3 kgf/cm2 , 52 to 62 psi) 631 to 731 kPa (6.4 to 7.5 kgf/cm2 , 92 to 106 psi)
      Stall 1,277 to 1,387 kPa (13.0 to 14.1 kgf/cm2, 185 to 201 psi) 1,462 to 1,670 kPa (14.9 to 17.0 kgf/cm2, 212 to 242 psi)

      Evaluation: 

      PROBLEM CHART

      Problem Possible Cause
      If measured values at all positions are higher than specified
      • Shift solenoid valve SLT defective
      • Regulator valve defective
      If measured values at all positions are lower than specified
      • Shift solenoid valve SLT defective
      • Regulator valve defective
      • Oil pump defective
      • O/D direct clutch defective
      If pressure is low when shift lever is on D only
      • D position circuit fluid leak
      • Forward clutch defective
      If pressure is low when shift lever is on R only
      • R position circuit fluid leak
      • Direct clutch defective
      • 1st & reverse brake defective
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