Operation CHARM: Car repair manuals for everyone.

Road Test

PROBLEM SYMPTOM CONFIRMATION

Taking into consideration the results of the customer problem analysis, try to reproduce the symptoms. If the problem is that the transaxle does not shift up, 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.

ROAD TEST

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

a. D position test:
Shift into the D position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.
Check that 1 -> 2, 2 -> 3, 3 -> 4 and 4 -> 5th up-shifts take place, and that the shift points conform to the automatic shift schedule.

HINT:
5th Gear Up-shift Prohibition Control
- Coolant temp. is 68°C (154°F) or less and vehicle speed is 70 km/h (43 mph) or less.
- ATF temp. is -2°C (28°F) or less.

4th Gear Up-shift Prohibition Control
- Coolant temp. is 65°C (149°F) or less and vehicle speed is 55 km/h (34 mph) or less.

5th and 4th Gear Lock-up Prohibition Control
- Brake pedal is depressed.
- Accelerator pedal is released.
- Coolant temp. 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 and 4 -> 5th up-shifts.

3. Check for abnormal noise and vibration.
Drive in the D position lock-up or 5th gear and check for abnormal noises and vibration.

HINT: The check for the cause of abnormal noise and vibration must be done very thoroughly as it could also be due to loss of balance in the differential, torque converter clutch, etc.

4. Check kick-down operation.
While running in the D position, 2nd, 3rd, 4th and 5th gears, check that the possible kick-down vehicle speed limits for 2 -> 1, 3 -> 2, 4 -> 3 and 5th -> 4 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 in D position 5th gear, at 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 in the 1st and 2nd gear.
- 4th lock-up operates while uphill-downhill control is active in D position.
- 3rd lock-up operates while uphill-downhill control is active.
- If there is a big jump in engine speed, there is no lock-up.

b. 4 position test:
Shift into the 4 position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.
Check that the 1 -> 2, 2 -> 3 and 3 -> 4 up-shift take place and that the shift point conforms to the automatic shift schedule.

HINT: There is no 5th up-shift in the 4 position.

2. Check engine braking.
While driving in the 4 position and 4th 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. 3 position test:
Shift into the 3 position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.
Check that the 1 -> 2 and 2 -> 3 up-shift take place and that the shift point conforms to the automatic shift schedule.

HINT: There is no 4th up-shift and lock-up in the 3 position.

2. Check engine braking.
While running in the 3 position and 3rd 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.

d. 2 position test:
Shift into the 2 position and fully depress the accelerator pedal and check the following points.

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 3rd up-shift and lock-up in the 2 position.

2. Check engine braking.
While running 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.

e. L position test:
Shift into the L position and fully depress the accelerator pedal and check the following points.

1. Check no up-shift.
While running in the L position, check that there is no up-shift to 2nd gear.

HINT: There is no lock-up in the L position.

2. Check engine braking.
While running in the L position, release the accelerator pedal and check the engine braking effect.

3. Check for abnormal noise during acceleration and deceleration.

f. R position test:
Shift into the R position and fully depress the accelerator pedal and check for slipping.

CAUTION: Before conducting this test ensure that the test area is free from people and obstruction.

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

h. Uphill/downhill control function test:

1. Check that the gear does not up-shift to the 4th or 5th gear while the vehicle is driving uphill.
2. Check that the gear automatically down-shifts from 5th to 4th or from the 4th to 3rd gear when brake is applied while the vehicle is driving downhill.