Hydraulic Test [09/2020 - ]

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PERFORM HYDRAULIC TEST

WARNING:

Do not perform a stall test if there are any people or objects near the vehicle.

Fig 1: Warning: Do Not Perform Stall Test With People Or Objects Near Vehicle
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
The vehicle could begin moving suddenly, resulting in a serious accident.

Do not perform a stall test if any wheel chocks are out of position.

Fig 2: Warning: Do Not Perform Stall Test If Wheel Chocks Are Out Of Position
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
The vehicle could begin moving suddenly, resulting in a serious accident.

Do not perform the stall test on a slippery or low-friction surface that could allow the tires to spin.

Fig 3: Warning: Do Not Perform Stall Test On Surfaces That Could Allow Tires To Spin
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
The vehicle could begin moving suddenly, resulting in a serious accident.

A line pressure test should always be performed with at least 2 people. One technician should observe the conditions of wheels or wheel stoppers outside the vehicle while the other is performing the test.

Measure the line pressure.

NOTE:

Perform this test with the ATF (Automatic Transmission Fluid) at the normal operating temperature: 50 to 80°C (122 to 176°F)
Be careful to prevent SST hose from contacting the exhaust pipe.
This check must be conducted after checking and adjusting engine.
Perform this test with the A/C off.
Do not perform the stall test for longer than 5 seconds.
When performing the stall speed test repeatedly, wait for 15 seconds or more between tests.
Perform this test with the AUTO function (shift-linked function) of the electric parking brake system off.

Warm up the ATF (Automatic Transmission Fluid).
Lift the vehicle up.
Remove the test plug on the center of the right side transmission case and connect SST.

Fig 4: Testing Line Pressure
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- SST: 09993-19016
  1. 09993-00011
  2. 09993-00041
Lower the vehicle.
Fully apply the parking brake and chock all 4 wheels.
HINT:

When the parking brake indicator (red) is illuminated after the electric parking brake switch assembly has been pushed to the lock side, the maximum amount of braking force is applied if the electric parking brake switch assembly is pushed to the lock side one more time.
Start the engine and check idling speed.
Keep the brake pedal firmly depressed with your left foot and move the shift lever to D.
Measure the line pressure when the engine is idling.
Depress the accelerator pedal all the way down. Quickly read the highest line pressure when engine speed reaches stall speed.

In the same manner, do the test with the shift lever in R.

Specified Line Pressure

Condition	Line Pressure
Condition	Shift lever in D	Shift lever in R
Idling	350 to 450 kPa (3.5 to 4.6 kgf/cm² , 50 to 65 psi)	450 to 600 kPa (4.5 to 6.1 kgf/cm² , 65 to 87 psi)
Stall test	1250 to 1450 kPa (12.7 to 14.8 kgf/cm² , 181 to 210 psi)	1450 to 1700 kPa (14.8 to 17.3 kgf/cm² , 210 to 247 psi)

EVALUATION:

Problem	Possible Cause
If the measured values at all position are higher	Shift solenoid valve (SLT) defective Regulator valve defective
If the measured values at all position 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 No. 1 clutch (C1) defective
If pressure is low in the R position only	R position circuit fluid leak No. 3 clutch (C3) defective No. 4 brake (B4) defective