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Hydraulic Test

  1. PERFORM HYDRAULIC TEST 
    1. Measure the line pressure.
      NOTE:
      • Perform the test at the normal operating ATF (Automatic Transmission Fluid) temperature: 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 the wheels or wheel stoppers from 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 the engine.
      • Perform the test with the A/C OFF.
      • When conducting the stall test, do not continue for more than 5 seconds.
      1. Warm up the ATF (Automatic Transmission Fluid).
      2. Turn the ignition switch OFF.
      3. Lift the vehicle up.
      4. Remove the test plug on the transmission case center right side and connect SST.

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

        Fig 1: Measuring Line Pressure With SST
        G05844310Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Lower the vehicle.
      6. Fully apply the parking brake and chock the 4 wheels.
      7. Start the engine and check the idling speed.
      8. Keep your left foot pressed firmly on the brake pedal and shift into the D position.
      9. Measure the line pressure when the engine is idling.
      10. Fully depress the accelerator pedal with your right foot. Quickly read the highest line pressure when the engine speed reaches stall speed
      11. In the same manner, do the test in the R position.

        Specified line pressure: 

        LINE PRESSURE SPECIFICATION

        Condition D position kPa (kgf/cm2 , psi) R position kPa (kgf/cm2 , psi)
        Idling 356 to 426 kPa (3 6 to 4 3 kgf/cm2 , 52 to 62 psi) 482 to 600 kPa (4 9 to 6 1 kgf/cm2 , 70 to 87 psi)
        Stall test 1284 to 1429 kPa (13 1 to 14 6 kgf/cm2 , 186 to 207 psi) 1290 to 1518 kPa (13 2 to 15 5 kgf/cm2 , 187 to 220 psi)

        Evaluation: 

        POSSIBLE CAUSE CHART

        Problem Possible cause
        If the measured values at both positions are higher
        • Shift solenoid valve (SLT) defective
        • Regulator valve defective
        If the measured values at both positions are lower
        • Shift solenoid valve (SLT) defective
        • Regulator valve defective
        • Oil pump defective
        If pressure is low in the D position only
        • D position circuit fluid leak
        • Clutch No 1 (C1 ) defective
        If pressure is low in the R position only
        • R position circuit fluid leak
        • Clutch No 3 (C3 ) defective
        • Brake No 4 (B4 ) defective
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