Automatic Transmission System Road Test

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.

D position test
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 and 3 → O/D up-shifts take place at the shift points shown in the automatic shift schedule.
   

   HINT:

   O/D Gear Up-shift Prohibition Control

   1. Engine coolant temperature is 47°C (117°F) or less and vehicle speed is 49 km/h (30 mph) or less.
      

   3rd Gear Up-shift Prohibition Control

   1. Engine coolant temperature is 40°C (104°F) or less and vehicle speed is 45 km/h (28 mph) or less.
      

   O/D Gear Lock-up Prohibition Control

   1. Brake pedal is depressed.
      
   2. Accelerator pedal is released.
      

2. Check for shift shock and slip.
   Check for shock and slip at the 1 → 2, 2 → 3 and 3 → O/D up-shifts.
   

3. Check for abnormal noise and vibration.
   Drive the vehicle in D lock-up or O/D and check for abnormal noises and vibrations.
   

   NOTICE:

   If abnormal noises and/or vibrations occur, perform 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 2nd, 3rd or O/D with the shift lever on D, check that the possible kick-down vehicle speed limits for the 2 → 1, 3 → 2 and O/D → 3 kick-downs conform to those indicated on the automatic shift schedule.
   

5. Check for abnormal shock and slip at kick-down.
   

6. Check the lock-up mechanism.
   Drive the vehicle in O/D with the shift lever on D. Maintain a steady speed (lock-up on) of about 80 km/h (50 mph). Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.
   

   HINT:

   If there is a sudden increase in engine speed, there is no lock-up.

2 position test
Move the shift lever to 2 and fully depress the accelerator pedal. Check the following:

1. Check up-shift operation.
   Check that the 1 → 2 up-shift takes place and that the shift point conforms to the automatic shift schedule.
   

   HINT:

   There is no 2 → 3 or 3 → O/D up-shift and no lock-up when the shift lever is on 2.

2. Check engine braking.
   While driving the vehicle in 2nd gear with the shift lever in the 2 position, release the accelerator pedal and check the engine braking effect.
   

3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
   

L position test
Move the shift lever to L and fully depress the accelerator pedal. Check the following:

1. Check that there is no up-shift.
   While driving the vehicle with the shift lever on L, check that there is no up-shift to 2nd gear.
   

2. Check engine braking.
   While driving the vehicle with the shift lever on L, release the accelerator pedal and check the engine braking effect.
   

3. Check for abnormal noises during acceleration and deceleration.
   

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.

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.