Road Test

A760F AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: 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 or shift down, or that the shift point is too high or too low, conduct the following road test while referring to the automatic shift schedule and reproduce the problem symptoms.

2. ROAD TEST

NOTICE:
Perform the test while the ATF temperature is 50 to 80°C (122 to 176°F).

(a) D position test

(1) Check up-shift operation.

Check the 1 -> 2, 2 -> 3, 3 -> 4, 4 -> 5 and 5-> 6 up-shifts.

HINT
6th Gear Up-shift Prohibition Control

* Engine coolant temperature is less than 60°C (140°F) and vehicle speed is less than 55 km/h (34 mph).
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).
Lock-up Prohibition Control

* Brake pedal is depressed.
* Accelerator pedal is released.
* Engine coolant temperature is less than 60°C (140°F).
* Lock-up in 5th or 6th gear is not engaged when the S4 range is selected.
* Lock-up in 6th gear is not engaged when the S5 range is selected.
* Lock-up in 3rd or 2nd gear is engaged when ATF temperature is more than 125°C (257°F).
* Lock-up control when accelerating is not engaged when the S1 range is selected, or in 1st gear.
(2) Check for shift shock and slippage.

Check for shock and slippage at the 1 -> 2, 2 -> 3, 3 -> 4, 4 -> 5 and 5-> 6 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, 4 -> 5 and 5-> 6 while driving with the shift lever in D, 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 that the 2 -> 1, 3 -> 2, 4 -> 3, 5 -> 4 and 6 -> 5 kick-downs take place when accelerating with the shift lever in D.

(5) Check for abnormal shock and slippage at each kick-down.

(6) Check the lock-up mechanism.

* Drive in 5th gear with the shift lever in D 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) S position test

(1) Check shift operation.

* While driving the vehicle at a vehicle speed of 100 km/h (62 mph) or less in 6th gear with the shift lever in D, move the shift lever to S and return it to D. Check that the gear change 6 -> 4 down-shift and 4 -> 6 up-shift can be performed.

* With the shift lever in S (while the vehicle is stopped), shift into the "+" position to check that the shift position on the combination meter changes as follows: 1 -> 2, 2 -> 3, 3 -> 4, 4 -> 5 and 5 -> 6.

* While driving the vehicle in 6th gear with the S6 range selected (at a vehicle speed of approximately 70 to 80 km/h (43 to 50 mph)), move the shift lever to "-" and check if the down-shift to 5th gear occurs and the engine brake operates properly.

* While driving the vehicle in 5th gear with the S5 range selected (at a vehicle speed of approximately 55 to 65 km/h (34 to 40 mph)), move the shift lever to "-" and check if the down-shift to 4th gear occurs and the engine brake operates properly.

* While driving the vehicle in 4th gear with the S4 range selected (at a vehicle speed of approximately 35 to 45 km/h (21 to 28 mph)), move the shift lever to "-" and check if the down-shift to 3rd gear occurs and the engine brake operates properly.

* While driving the vehicle in 3rd gear with the S3 range selected (at a vehicle speed of approximately 20 to 30 km/h (12 to 19 mph)), move the shift lever to "-" and check if the down-shift to 2nd gear occurs and the engine brake operates properly.

* While driving the vehicle in 2nd gear with the S2 range selected (at a vehicle speed of approximately 10 to 20 km/h (6 to 12 mph)), move the shift lever to "-" and check if the down-shift to 1st gear occurs and the engine brake operates properly.

HINT
Manual shifting (S range) is prohibited under either of the following conditions:

* Down-shifting that causes engine overrun.
* The driver continuously down-shifts (down-shifting to 1st gear may not be performed).
(c) R position test

Move the shift lever to R, lightly depress the accelerator pedal, and check that the vehicle moves backward without any abnormal noise or vibration.

CAUTION:
Before conducting this test, make sure that the test area is free from people and obstructions.

(d) P position test

Stop the vehicle on an incline (more than 5°) and after moving the shift lever to P, release the parking brake. Check that the parking lock pawl holds the vehicle in place.