Road Test

PROBLEM SYMPTOM CONFIRMATION

Try to reproduce the symptoms according to customer problem analysis.

If the problem is that the transaxle does not up-shift, down-shift, 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.

ROAD TEST

NOTE: Perform the test with the Automatic Transmission Fluid (ATF) temperature at 50 to 80 °C (122 to 176 °F) in the normal operation.

a. D position test
Move the shift lever into the D position, depress the accelerator pedal fully and then check the following points:

1. Check the up-shift operation.
The up-shift operation, such as 1 --> 2, 2 --> 3 and 3 --> O/D, takes place at the shift point shown in the automatic shift schedule.

HINT:
- O/D Gear Up-shift Prohibition Control
1. Engine coolant temperature is 60 °C (140 °F) or less.
2. If there is a difference of 10 km/h (6 mph) between the set cruise control speed and actual vehicle speed.

- O/D Gear Lock-up Prohibition Control
1. Brake pedal is depressed.
2. Coolant temperature is 60 °C (140 °F) or less.

2. Check for shift shock and slip.
Check for shock and slip at the up-shift operation of 1 --> 2, 2 --> 3 and 3 --> O/D.
3. Check for abnormal noise and vibration.
Run the vehicle in the D position lock-up or O/D gear and check for abnormal noise and vibration.

HINT: Check the cause of abnormal noise and vibration very thoroughly, as it could be due to the loss of balance in the differential torque converter clutch, etc.

4. Check the kick-down operation.
While running the vehicle in the D position, 2nd, 3rd or O/D gears, check that the possible kick-down vehicle speed limits of 2 --> 1, 3 --> 2 and O/D --> 3 kick-downs conform to those indicated on the automatic shift schedule.
5. Check abnormal shock and slip at kick-down.
6. Check the lock-up mechanism.
- Drive the vehicle in the D position or O/D gear at steady speed (lock-up ON) of about 60 km/h (37 mph).
- Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.

If there is a big jump in the engine speed, there is no lock-up.

b. 2 position test
Move the shift lever into the 2 position, depress the accelerator pedal fully and check the following points:
1. Check up-shift operation.
Check that the up-shift operation of 1 --> 2 up-shift takes place and that the shift point conforms to the automatic shift schedule.

HINT: There is no O/D up-shift and lock-up in the 2 position.

2. Check the engine braking.
While running the vehicle in the 2 position and 2nd gear, release the accelerator pedal and check the engine braking effect.
3. Check for abnormal noise during acceleration and deceleration, and for shock at up-shift and down-shift.

c. L position test
Move the shift lever into the 2 position, depress the accelerator pedal fully and check the following points:
1. Check no up-shift.
While running the vehicle in the L position, check that there is no up-shift to the 2nd gear.
2. Check the engine braking.
While running the vehicle in the L position, release the accelerator pedal and check the engine braking effect.
3. Check for abnormal noise during acceleration and deceleration.

d. R position test
Shift into the R position, lightly depress the accelerator pedal, and check that the vehicle moves backward without any abnormal noise or vibration.

CAUTION: Before conducting this test, ensure that the test area is kept away from people and obstructions.

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