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Road Test

  1. PROBLEM SYMPTOM CONFIRMATION 
    1. Based on the result of the customer problem analysis, try to reproduce the symptoms. If the problem is that the transmission does not shift up or shift down, or the shift point is too high or too low, conduct the following road test referring to the automatic shift schedule and simulate the problem symptoms.
  2. ROAD TEST 
    NOTE: Perform the test at the ATF (Automatic Transmission Fluid) temperature 50 to 80°C (122 to 176°F) in the normal operation.
    1. D position test (NORM and PWR pattern) Move the shift lever to D and fully depress the accelerator pedal. Check the following:
      1. Check up-shift operation.

        Check that the 1 → 2, 2 → 3, 3 → 4, 4 → 5, 5 → 6, 6 → 7 and 7 → 8 up-shifts take place at the shift points shown in the automatic shift schedule (see AA80E AUTOMATIC TRANSMISSION ).

        HINT:

        Lock-up Prohibition Control

        • Brake pedal is depressed.
        • Accelerator pedal is released.
        • Engine coolant temperature is 60°C (140°F) or less.
      2. Check for shift shock and slip.

        Check for shock and slip at the 1 → 2, 2 → 3, 3 → 4, 4 → 5, 5 → 6, 6 → 7 and 7 → 8 up-shifts.

      3. Check for abnormal noise and vibration.

        Check for abnormal noise and vibration when up-shifting from 1 → 2,2 → 3,3 → 4,4 → 5, 5 → 6, 6 → 7 and 7 → 8 while driving with the shift lever on D, and check while driving in the lockup condition.

        NOTE: If abnormal noise and/or vibration occur, conduct a thorough check of the cause. Failure to repair the problem may lead to subsequent problems in the differential, torque converter, etc.
      4. Check kick-down operation.

        While driving the vehicle in the 2nd, 3rd, 4th, 5th and 6th gears with the shift lever on D, check that the possible kick-down vehicle speed limits for the 2 → 1, 3 → 2,4 → 3, 5 → 4,6 → 5, 7 → 6 and 8 → 7 kick-downs conform to those indicated in the automatic shift schedule (see AA80E AUTOMATIC TRANSMISSION ).

      5. Check for abnormal shock and slip at kick-down.
      6. Check the lock-up mechanism.
        • Drive the vehicle in the 6th, 7th or 8th gear with the shift lever on D. Maintain a steady speed (lock-up ON).
        • Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.

          HINT:

          • There is no lock-up function in the 1st, 2nd, 3rd, 4th and 5th gears.
          • If there is a sudden increase in engine speed, there is no lock-up.
    2. S position test
      1. Check shift operation (when the vehicle is stopped)
        • When the engine switch is on (IG) and the shift lever is moved from D to S, check that the combination meter's shift range display indicates "4".
        • After performing the operation above, check that the shift range display decreases or increases by 1 when the shift lever is moved to "-" or "+", respectively.

          HINT:

          • If the shift lever is held in "+" for more than 1 second, the shift range display will change to 8.
          • If the shift range display is 6, 7 or 8, moving the shift lever to "-" will change the display to 4.
      2. Check shift operation (when the vehicle is being driven)
        • Initial shift range when shifting from D to S: Depending on the vehicle speed, the initial shift range will be as shown in the table below when shifting from D to S.
          VEHICLE SPEED REFERENCE CHART

          Vehicle speed when shifting from D to S km/h (mph) 0 to 58 (0 to 36) 58 to 64 (36 to 40) 64 to 82 (40 to 51) 82 to 89 (51 to 55) 89 to 190 (55 to 118) 190 to 202 (118 to 126) 202 or more (126 or more)
          Initial shift range when shifting to S 4 4 or 5*1 5 5 or 6*1 6 6 or 7*1, *2 7*2

        Example: 

        • When the vehicle is being driven at approximately 0 to 64 km/h (0 to 40 mph) and the shift lever is moved from D to S, check that the combination meter's shift range display indicates "4".
        • When the vehicle is being driven at approximately 58 to 89 km/h (36 to 55 mph) and the shift lever is moved from D to S, check that the combination meter's shift range display indicates "5".
        • When the vehicle is being driven at approximately 82 to 202 km/h (51 to 126 mph) and the shift lever is moved from D to S, check that the combination meter's shift range display indicates "6".
        • When the vehicle is being driven at approximately 190 to 202 km/h (118 to 126 mph) and the shift lever is moved from D to S, check that the combination meter's shift range display indicates "7".*2
        NOTE:
        • *1: At certain speeds, differences in tire sizes, etc. cause the "Initial shift range when shifting to S" value to have 2 possibilities.
        • *2: Normally, in countries or areas where regulations do not permit driving at more than 200 km/h (124 mph), the initial shift range will never be "7".
        • Due to the vehicle speed related "engine over revving prevention" when shifting to S to prevent over revving the engine when the shift lever is moved to "-", the shift range will not decrease as shown when the actual vehicle speed is above the range shown.
        VEHICLE SPEED REFERENCE CHART

        Shift Range Decrease 2 to 1 3 to 2 4 to 3 5 to 4 6 to 5
        Vehicle speed at which shift range decrease is permitted km/h (mph)(1) 38 to 44 (24 to 27) 78 to 85 (48 to 53) 129 to 141 (80 to 88) 167 to 180 (104 to 112) 201 to 214 (125 to 133)
        (1) Differences in tire sizes, etc. cause the "Vehicle speed at which shift range decrease is permitted" to have a range, as shown above.
        • To prevent over revving when driving with the shift lever on S, if the vehicle speed is within the vehicle speeds shown in the table below, the gear will increase.
          SHIFT RANGE REFERENCE

          Shift Range Vehicle speed necessary for shift range Increase km/h (mph)(1) Gear
          1 64 to 75 (40 to 47) 1 to 2
          2 95 to 106 (59 to 66) 2 to 3
          3 134 to 150 (83 to 93) 3 to 4
          4 164 to 186 (102 to 116) 4 to 5
          5 206 to 223 (128 to 139) 5 to 6
          (1) Differences in tire sizes, etc. cause the "Vehicle speed necessary for shift range increase" to have a range, as shown above.
        • When moving the shift lever to "-", the resulting range and gear are determined based on the range and gear prior to moving the shift lever.
          SHIFT RANGE REFERENCE

              Range before moving shift lever to "-"
              8 7 6 5 4 3 2 1
          Gear before moving shift lever to "-" 8th 7 range 7th gear - - - - - - -
          7th 6 range 6th gear 6 range 6th gear - - - - - -
          6th 5 range 5th gear 5 range 5th gear 5 range 5th gear - - - - -
          5th 4 range 4th gear 4 range 4th gear 4 range 4th gear 4 range 4th gear - - - -
          4th 4 range 4th gear 4 range 4th gear 4 range 4th gear 4 range 4th gear 3 range 3th gear - - -
          3rd 4 range 3rd gear 4 range 3rd gear 4 range 3rd gear 4 range 3rd gear 3 range 3rd gear 2 range 2nd gear - -
          2nd 4 range 2nd gear 4 range 2nd gear 4 range 2nd gear 4 range 2nd gear 3 range 2nd gear 2 range 2nd gear 1 range 1st gear -
          1st 4 range 1st gear 4 range 1st gear 4 range 1st gear 4 range 1st gear 3 range 1st gear 2 range 1st gear 1 range 1st gear 1 range 1st gear

        Example: 

        • When moving the shift lever to "-" while the shift range is 6 and in 6th gear, the shift range changes to 5 and the gear to 5th.
        • When moving the shift lever to "-" while the shift range is 6 and in 3rd gear, the shift range changes to 4, but the gear remains in 3rd.
        • When moving the shift lever to "-" while the shift range is 4 and in 4th gear, the shift range remains on 4, but the gear changes to 3rd.
        • When moving the shift lever to "-" while the shift range is 4 and in 3rd gear, the shift range changes to 3, but the gear remains in 3rd.
    3. R position test

      Move the shift lever to R and lightly depress the accelerator pedal. Check that the vehicle moves backward without any abnormal noise or vibration.

      CAUTION: Before conducting this test, ensure that no people or obstacles are in the test area.
    4. P position test

      Stop the vehicle on an incline (more than 5°). Then move the shift lever to P and release the parking brake. Check that the parking lock pawl holds the vehicle in place.