AUTOMATIC TRANSMISSION SYSTEM MECHANICAL SYSTEM TESTS


  1. STALL SPEED TEST

    Tech Tips

    This test is to check the overall performance of the engine and transmission.

    CAUTION:


    • This test should be done on a paved surface (a surface that is not slippery).

    • To ensure safety, perform this test in an open and level area that provides good traction.

    • The stall speed test should always be performed with at least 2 people. One person should observe the condition of the wheels and wheel chocks while the other is performing the test.

    Note


    • Do not perform the stall speed test for more than 5 seconds.

    • When performing the stall speed test more than once, make sure to wait 15 seconds or more between tests.

    • Perform the test at the normal operating ATF temperature of 50 to 80°C (122 to 176°F).


    1. Connect the GTS to the DLC3.

    2. Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).

    3. Allow the engine to idle with the air conditioning off.

    4. Chock all 4 wheels.

    5. Set the parking brake and keep the brake pedal depressed firmly with your left foot.

    6. Move the shift lever to D.

    7. Depress the accelerator pedal as much as possible with your right foot.

    8. Read the engine speed (stall speed) and release the accelerator pedal immediately.

      Evaluation
      Test Result Possible Cause
      Stall speed is lower than standard value

      • Stator one-way clutch is not operating properly

      • Torque converter assembly is faulty (stall speed is less than standard value by 600 rpm or more)

      • Engine power may be insufficient
      Stall speed is higher than standard value

      • Line pressure is low

      • C1 clutch slipping

      • F3 one-way clutch is not operating properly

      • F4 one-way clutch is not operating properly

  • SHIFT TIME LAG TEST

    Tech Tips

    When the shift lever is moved while the engine is idling, there will be a certain time elapse or lag before shock can be felt. This is used for checking the condition of the direct clutch, forward clutch, 1st brake and reverse brake.


    1. Connect the GTS to the DLC3.

    2. Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).

    3. Allow the engine to idle with the air conditioning off.

    4. Set the parking brake and keep the brake pedal depressed firmly.

    5. Check the D position time lag.


      1. Move the shift lever to N and wait for 1 minute.

      2. Move the shift lever to D and measure the time until the shock is felt.

      3. Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.

    6. Check the R position time lag.


      1. Move the shift lever to N and wait for 1 minute.

      2. Move the shift lever to R and measure the time until the shock is felt.

      3. Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.

        Evaluation
        Test Result Possible Cause
        D position time lag exceeds standard value

        • Line pressure is low

        • C1 clutch is worn

        • F3 one-way clutch is not operating properly

        • F4 one-way clutch is not operating properly
        R position time lag exceeds standard value

        • Line pressure is low

        • C3 clutch is worn

        • B4 brake is worn

        • F1 one-way clutch is not operating properly