ELECTRONIC CONTROLLED 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, 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 |
D position test
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 up-shifts take place at the shift point shown in the automatic shift schedule (Click here).
Check for shift shock and slip.
Check for shock and slip at the 1 → 2, 2 → 3, 3 → 4 and 4 → 5 up-shifts.
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 on D, and check while driving in the lock-up condition.
Check kick-down operation.
While driving the vehicle in the 2nd, 3rd, 4th and 5th gears with the shift lever on D, check that the possible kick-down vehicle speed limits for 2 → 1, 3 → 2, 4 → 3 and 5 → 4 kick-downs conform to those indicated on the automatic shift schedule (Click here).
Check for abnormal shock and slip at kick-down.
Check the lock-up mechanism.
Drive the vehicle in the 5th gear with the shift lever on D. Maintain a steady speed (lock-up ON) of about 80 km/h (50 mph). Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.
4 position test
Move the shift lever to 4 and fully depress the accelerator pedal. Check the following:
Check up-shift operation.
Check that the 1 → 2, 2 → 3, and 3 → 4 up-shift takes place and that the shift point conforms to the automatic shift schedule (Click here).
Check engine braking.
While driving the vehicle in 4th gear with the shift lever is on 4, release the accelerator pedal and check the engine braking effect.
Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
Check the lock-up mechanism.
3 position test
Move the shift lever to 3 and fully depress the accelerator pedal. Check the following:
Check up-shift operation.
Check that the 1 → 2 and 2 → 3 up-shifts take place and that the shift point conforms to the automatic shift schedule (Click here).
Check engine braking.
While driving the vehicle in 3rd gear with the shift lever is on 3, release the accelerator pedal and check the engine braking effect.
Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
2 position test
Move the shift lever to 2 and fully depress the accelerator pedal. Check the following:
Check up-shift operation.
Check that the 1 → 2 up-shift takes place and that the shift point conforms to the automatic shift schedule (Click here).
Check engine braking.
While driving the vehicle in 2nd gear with the shift lever is on 2, release the accelerator pedal and check the engine braking effect.
Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
L position test
Move the shift lever to L and fully depress the accelerator pedal. Check the following:
Check that there is no up-shift.
While driving the vehicle with the shift lever is on L, check that there is no up-shift to 2nd gear.
Check engine braking.
While driving the vehicle with the shift lever is on L, release the accelerator pedal and check the engine braking effect.
Check for abnormal noises during acceleration and deceleration.
R position test
Move the shift lever to R and lightly depress the accelerator pedal. Check that the vehicle moves back ward without any abnormal noise or vibration.
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.