Road Test

A750E AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM (for 1GR-FE): ROAD TEST

ROAD TEST

1. PROBLEM SYMPTOM CONFIRMATION
(a) 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, 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 normal operating ATF temperature of 50 to 80°C (122 to 176°F).

(a) D position test
Shift into the D position, fully depress the accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1 -> 2, 2 -> 3, 3 -> 4 and 4 -> 5 up-shifts take place at the shift points shown in the automatic shift schedule Service Data.

HINT:
5th Gear Up-shift Prohibition Control
- Engine coolant temperature is less than 55°C (131°F) and vehicle speed is less than 51 km/h (32 mph).
4th Gear Up-shift Prohibition Control
- Engine coolant temperature is less than 47°C (117°F) and vehicle speed is less than 49 km/h (30 mph).
5th Gear Lock-up Prohibition Control
- Brake pedal is depressed.
- Accelerator pedal is released.
- Engine coolant temperature is less than 60°C (140°F).
(2) Check for shift shock and slippage.
Check for shock and slippage at the 1 -> 2, 2 -> 3, 3 -> 4 and 4 -> 5 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 and 4 -> 5 while driving with the shift lever in the D position, and also check while driving in the lock-up condition.

HINT:
The check for the cause of abnormal noise and vibration must be done thoroughly as it could also be due to loss of balance in the differential, torque converter clutch, etc.
(4) Check kick-down operation.
Check vehicle speeds when the 2nd to 1st, 3rd to 2nd, 4th to 3rd, and 5th to 4th kick-downs take place while driving with the shift lever in the D position. Confirm that each speed is within the applicable vehicle speed range indicated in the automatic shift schedule Service Data.
(5) Check for abnormal shock and slippage at kick-down.
(6) Check the lock-up mechanism.

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

(b) 4 (O/D OFF) position test
Shift into the 4 (O/D OFF) position, 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-shifts take place and that the shift points conform to the automatic shift schedule Service Data.

HINT:
- There is no 4 -> 5 up-shift in the 4 position.
- 4th Gear Lock-up Prohibition Control

- Brake pedal is depressed.
- Accelerator pedal is released.
- Engine coolant temperature is less than 60°C (140°F).

(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 noises during acceleration and deceleration, and for shock at up-shift and down-shift.
(4) Check the lock-up mechanism.

- Drive in the 4 position and 4th gear, at a steady speed (lock-up ON).
- 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.

(c) 3 position test
Shift into the 3 position, fully depress the accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1 -> 2 and 2 -> 3 up-shifts take place and that the shift points conform to the automatic shift schedule Service Data.

HINT:
There is no 3 -> 4 up-shift or lock-up in the 3 position.
(2) Check engine braking.
While driving in the 3 position and 3rd gear, 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.
(d) 2 position test
Shift into the 2 position, 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 Service Data.

HINT:
There is no 2 -> 3 up-shift or lock-up in the 2 position.
(2) Check engine braking.
While driving in the 2 position and 2nd gear, 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.
(e) L position test
Shift into the L position, fully depress the accelerator pedal and check the following points.
(1) Check no up-shift.
While driving in the L position, check that there is no up-shift to 2nd gear.
(2) Check engine braking.
While driving in the L position, release the accelerator pedal and check the engine braking effect.
(3) Check for abnormal noises during acceleration and deceleration.
(f) 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 free from people and obstructions.

(g) P position test
Stop the vehicle on an incline (more than 5°) and after shifting into the P position, release the parking brake. Then, check that the parking lock pawl holds the vehicle in place.