Road Test

PROBLEM SYMPTOM CONFIRMATION

Taking into consideration the results of the customer problem analysis, try to reproduce the symptoms of the trouble. If the problem is that the transaxle does not up-shift, does not down-shift, or the shift point is too high or too low, conduct the following road test to confirm the automatic shift schedule and simulate the problem symptoms.

ROAD TEST

NOTE: Perform the test at normal operating ATF temperature 50 - 80 °C (122 - 176 °F).

a. D position test in NORM and PWR ranges:
Shift into the D position and hold the accelerator pedal constant at the fully throttle valve opening position.
1. Check to see that 1 -> 2, 2 -> 3 and 3 -> O/D up-shifts should take place, and that the shift positions conform to the automatic shift schedule .

HINT:
- There is not O/D up-shift and lock-up when the engine coolant temperature is below 60 °C (140 °F).
- There is not lock-up when the vehicle speed is 10 kph (6 mph) less than the set cruise control speed.




Evaluation:

2. In the same way, check the shock and slip at the 1 -> 2, 2 -> 3 and 3 -> O/D up-shifts.




Evaluation:

3. Run at the D position lock-up or O/D gear and check for abnormal noises and vibration.

HINT: The check for the cause of any abnormal noise and vibration must be made with extreme care as it could also be due to loss of balance in the drive shaft, tire, and torque converter clutch, etc.

4. While running in the D position, 2nd, 3rd and O/D gears, check to see that the possible kick-down vehicle speed limits for 2 -> 1, 3 -> 2 and O/D -> 3 kick-downs conform to those indicate the automatic shift schedule.
5. Check for abnormal shock and slip at kick-down.
6. Check for the lock-up mechanism.
- Drive in the D position, O/D gear, at a steady speed (lock-up ON) of about 75 kph (47 mph).
- Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.
If there is a big jump in engine speed, there is no lock-up.

b. 2 position test:
Shift into the 2 position and, while driving with the accelerator pedal held constantly at the full throttle valve opening position, push in one of the pattern selectors and check on the following points.
1. Check to see that the 1 -> 2 up-shift takes place and that the shift point conforms to that shown on the automatic shift schedule .
2. While running in the 2 position and 2nd gear, release the accelerator pedal and check the engine braking effect.




Evaluation:

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

c. L position test:
1. While running in the L position, check to see that there is no up-shift to 2nd gear.
2. While running in the L position, release the accelerator pedal and check the engine braking effect.




Evaluation:

3. Check for abnormal noises during acceleration and deceleration.

d. R position test:
Shift into the R position and when starting at fully throttle, check for slipping.

CAUTION: Before conducting this test ensure that the test area is free from personnel and obstructions.

e. P position test:
Stop the vehicle on a grade (more than 5°) and after shifting into the P position, release the parking brake. Then check to see that the parking lock pawl holds the vehicle in place.