HYDRAULIC PRESSURE TEST



This test measures the line pressure when the selector lever is in the D or R position with the engine idling or stalled. With this test, the operation status of the transmission components can be checked.
1.
warning For safety, operators must not stand in front of and at the rear of the vehicle during this test.
Check the ATF temperature.

  • ATF temperature: 50 - 80 °C
  • Switches for air conditioner, lamps, and others shall be OFF.
note Use the M.U.T.-III to measure the ATF temperature.
2.Raise the vehicle.
3.Remove the plug from the line pressure take off port.

4.Install special tools as shown in the figure and place the meter inside vehicle.

  • Oil pressure gauge <3.0 MPa> (MD998330)
  • Adapter (MD998920)
5.Pull the parking brake lever, and then fully depress the brake pedal.
6.Start the engine.
7.
caution
  • Do not maintain the WOT condition for 5 seconds or longer.
  • When successively performing the test under the stall state, only perform the test after checking that the fluid temperature is not at 80°C or more. If the fluid temperature exceeds 80°C, perform the test after running the engine at around 1,000 r/min for 1 minute or longer and then cooling the ATF to 80°C or less.
8.Shift the selector lever to D and R, and measure the idle state line pressure and stall state line pressure.
Standard value:
Item
Line pressure (MPa)
D
R
Idling
0.36 - 0.43
0.44 - 0.64
Stall
1.28 - 1.46
1.18 - 1.40

HYDRAULIC PRESSURE TEST JUDGEMENT


Hydraulic pressure test result
Probable cause
Both D and R are higher than the standard value.

  • Malfunction of line pressure control solenoid
  • Malfunction of primary regulator valve

Both D and R are less than the standard value.

  • Malfunction of line pressure control solenoid
  • Malfunction of primary regulator valve
  • Malfunction of oil pump

Only D is lower than the standard value.

  • Malfunction in D hydraulic circuit
  • Malfunction of clutch No.1

Only R is lower than the standard value.

  • Malfunction in R hydraulic circuit
  • Malfunction of clutch No.3
  • Malfunction of brake No.4