AUTOMATIC TRANSMISSION SYSTEM ROAD TEST
-
PROBLEM SYMPTOM CONFIRMATION
-
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 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 an ATF (Automatic Transmission Fluid) temperature 60 to 110°C (140 to 230°F) during normal operation.
-
D position test (NORM and SPORT pattern)
Move the shift lever to D and fully depress the accelerator pedal. Check the following:
-
Check up-shift operation.
Check that the 1 → 2, 2 → 3, 3 → 4, 4 → 5, 5 → 6, 6 → 7 and 7→ 8 up-shifts take place at the shift points shown in the automatic shift schedule.
Tech Tips
7th and 8th Gear Up-shift Prohibition Control
-
Engine coolant temperature is less than 45°C (113°F) and vehicle speed is less than 55 km/h (34 mph).
6th Gear Up-shift Prohibition Control
-
Engine coolant temperature is less than 45°C (113°F) and vehicle speed is less than 51 km/h (32 mph).
5th Gear Up-shift Prohibition Control
-
Engine coolant temperature is less than 45°C (113°F) and vehicle speed is less than 49 km/h (30 mph).
4th Gear Up-shift Prohibition Control
-
Engine coolant temperature is less than 45°C (113°F) and vehicle speed is less than 45 km/h (28 mph).
Lock-up Prohibition Control
-
Brake pedal is depressed.
-
Accelerator pedal is released.
-
Engine coolant temperature is 60°C (140°F) or less.
-
-
Check for shift shock and slippage.
Check for shock and slippage at the 1 → 2, 2 → 3, 3 → 4, 4 → 5, 5 → 6, 6 → 7 and 7 → 8 up-shifts.
-
Check for abnormal noise and vibration.
Check for abnormal noise and vibration when up-shifting from 1 → 2, 2 → 3, 3 → 4, 4 → 5, 5 → 6, 6 → 7 and 7 → 8 while driving with the shift lever in D, and check while driving with lock-up on.
Note
If abnormal noise and/or vibration occur, conduct a thorough check of the cause. Failure to repair the problem may lead to subsequent problems in the differential, torque converter, etc.
-
Check kick-down operation.
While driving the vehicle in 2nd, 3rd, 4th, 5th, 6th, 7th and 8th gears with the shift lever in D, check that the possible kick-down vehicle speed limits for the 2 → 1, 3 → 2, 4 → 3, 5 → 4, 6 → 5, 7 → 6 and 8 → 7 kick-downs conform to those indicated in the automatic shift schedule.
-
Check for abnormal shock and slippage at kick-down.
-
Check the lock-up mechanism.
-
Drive the vehicle in 6th, 7th or 8th gear with the shift lever in D. Maintain a steady speed (lock-up ON).
-
Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.
Tech Tips
-
There is no lock-up function in 1st, 2nd, 3rd, 4th and 5th gears when the shift lever is in D.
-
If there is a sudden increase in engine speed, there is no lock-up.
-
-
-
D position (fixed range mode) test
-
Check paddle switch operation
Tech Tips
When the vehicle is being operated in D position (fixed range mode), if the vehicle is stopped or the accelerator pedal is kept steady for a certain period of time with the transmission in the same gear, the vehicle will change back automatically to normal D position operation.
-
Initial shift range when the "-" paddle switch is operated with the shift lever in D:
The initial shift range selected is based on vehicle speed and the gear that was in use prior to operating the "-" paddle switch. In the following 2 tables, based on the gear in use and vehicle speed, there may be 2 different possible initial shift ranges. The range that will be selected is the lower of the 2.
Table 1 Vehicle speed
km/h (mph)
0 to 58 (0 to 36) 58 to 65 (36 to 40) 65 to 83 (40 to 52) 83 to 90 (52 to 56) Initial shift range when operating "-" paddle switch D4 D4 or D5 D5 D5 or D6 Table 2 Gear in use when driving in D position 1st 2nd 3rd 4th 5th 6th 7th 8th Initial shift range D1 D1 D2 D3 D4 D5 D6 D7
-
Engine over-revving prevention when in D position (fixed range mode):
To prevent engine over-revving when the "-" paddle switch is operated, selection of lower shift ranges will not be performed when the actual vehicle speed is greater than the speed ranges shown below.
Range Decrease D2 to D1 D3 to D2 Vehicle speed at which range decrease is permitted
km/h (mph)*
38 to 44 (24 to 27) 71 to 78 (44 to 48) Note
*: Differences in tire sizes, etc. cause the "Vehicle speed at which shift range decrease is permitted" to have a range, as shown above.
-
The shift range and gear when the "-" paddle switch is operated will be selected based on the shift range and gear that were in use before operating the "-" paddle switch.
Range before operating the "-" paddle switch D8 D7 D6 D5 D4 D3 D2 D1 Gear before operating the "-" paddle switch 8th D7 range
7th gear
- - - - - - - 7th D6 range
6th gear
D6 range
6th gear
- - - - - - 6th D5 range
5th gear
D5 range
5th gear
D5 range
5th gear
- - - - - 5th D4 range
4th gear
D4 range
4th gear
D4 range
4th gear
D4 range
4th gear
- - - - 4th D4 range
4th gear
D4 range
4th gear
D4 range
4th gear
D4 range
4th gear
D3 range
3rd gear
- - - 3rd D4 range
3rd gear
D4 range
3rd gear
D4 range
3rd gear
D4 range
3rd gear
D3 range
3rd gear
D2 range
2nd gear
- - 2nd D4 range
2nd gear
D4 range
2nd gear
D4 range
2nd gear
D4 range
2nd gear
D3 range
2nd gear
D2 range
2nd gear
D1 range
1st gear
- 1st D4 range
1st gear
D4 range
1st gear
D4 range
1st gear
D4 range
1st gear
D3 range
1st gear
D2 range
1st gear
D1 range
1st gear
D1 range
1st gear
-
When the "-" paddle switch is operated with the D6 range selected and the transmission in 6th gear, the D5 range and 5th gear will be selected.
-
When the "-" paddle switch is operated with the D6 range selected and the transmission in 3rd gear, the D4 range and 3rd gear will be selected.
-
When the "-" paddle switch is operated with the D4 range selected and the transmission in 4th gear, the D3 range and 3rd gear will be selected.
-
When the "-" paddle switch is operated with the D4 range selected and the transmission in 3rd gear, the D3 range and 3rd gear will be selected.
Example:
-
-
-
M position test
-
Check shift operation
Note
If the shift lever is moved from D to M during the system check that occurs after the engine switch is turned on (IG), both D position control and the D indication on the shift range indicator will continue until the system is confirmed to be normal.
If the shift lever is moved from D to M after the system check completes, M position control will be performed.
-
Check that no gear shift occurs when the shift position is changed from D to M while driving.
-
Engine over-revving prevention when the shift lever is in M:
To prevent engine over-revving, selection of lower gears will not be performed when the actual vehicle speed is greater than the speed ranges shown below.
Gear Decrease 2 to 1 Vehicle speed at which gear decrease is permitted
km/h (mph)*
38 to 57 (24 to 35) Note
*: Differences in tire sizes, etc. cause the "Vehicle speed at which gear decrease is permitted" to have a range, as shown above.
-
While driving with the shift lever in M, selection of lower gears will automatically be performed when the vehicle speed drops below the speed ranges shown below.
Gear 2 to 1 3 to 2 4 to 3 5 to 4 6 to 5 7 to 6 8 to 7 Vehicle speed for each automatic downshift
km/h (mph)*
10 to 15 (6 to 9) 15 to 20 (9 to 12) 35 to 41 (22 to 25) 42 to 48 (26 to 30) 53 to 59 (33 to 37) 56 to 62 (35 to 39) 67 to 74 (42 to 46) Note
*: Differences in tire sizes, etc. cause the "Vehicle speed for each automatic downshift" to have a range, as shown above.
-
-
-
R position test
Move the shift lever to R and lightly depress the accelerator pedal. Check that the vehicle moves backward without any abnormal noise or vibration.
CAUTION:
Before conducting this test, ensure that no people or obstacles are in the test area.
-
P position test
Stop the vehicle on an incline (more than 5°). Then move the shift lever to P and release the parking brake. Check that the parking lock pawl holds the vehicle in place.
-