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.

    Note


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

    • 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.


    1. Connect the intelligent tester to the DLC3.

    2. Run the vehicle until the ATF 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 the drive position.

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

    8. Read the engine rpm (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 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

      • F2 one-way clutch is not operating properly

      • O/D one-way clutch is not operating properly

Note

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

  • SHIFT TIME LAG TEST

    Tech Tips

    This test is to check the condition of the direct clutch, forward clutch, 1st brake and reverse brake.


    1. Connect the intelligent tester to the DLC3.

    2. Run the vehicle until the ATF 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 range 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 range 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 range time lag exceeds standard value

        • Line pressure is low

        • C1 clutch is worn

        • F2 one-way clutch is not operating properly

        • O/D one-way clutch is not operating properly
        R range 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