Problem Symptom Confirmation (Road Test)

PROBLEM SYMPTOM CONFIRMATION
Taking into consideration the results of the customer problem analysis, try to reproduce the symptoms of the trouble. If the problem is that the transmission does not up-shift, does not down-shift, or the shift point is too high or too low, conduct the following road test to confirm the automatic shift schedule and simulate the problem symptoms.

ROAD TEST

NOTICE: Perform the test at normal ATF operating temperature (50-80°C / 122-176°F).

1. D POSITION TEST (NORM AND PWR PATTERN)
Shift into the D position and keep the accelerator pedal constant at the full throttle valve opening position, and check the following points:
- Check up-shift operation: check that 1 - 2, 2 - 3 and 3 - O/D up-shift takes place, at the shift point show in the automatic shift schedule.




Conduct a test under both Normal and Power patterns.

HINT:
- O/D up-shift or lock-up will not occur when the coolant temp. is below 60°C (140°F) and speed is under 60 km/h (37 mph), or if there is a 10 km/h (6 mph) difference between the set cruise control speed.
- 3rd up-shift or lock-up will not occur when coolant temp. is below 35°C (95°F) and speed is under 40 km/h (25 mph).




- Check for shift shock and slip: check for shock and slip at the 1 - 2, 2 - 3 and 3 - O/D up-shifts.




- Check for abnormal noise and vibration: Run at the D Position lock-up or O/D gear and check for abnormal noise and vibration.

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




- Check kick-down operation: while running in the D position, 2nd, 3rd and O/D gears, check to see that possible kick-down vehicle speed limits for 2 - 1, 3 - 2 and O/D - 3 kick-downs conform to those indicated on the automatic shift schedule.
- Check abnormal shock and slip at kick-down.




- Check the lock-up mechanism
- Drive in D position, O/D gear, at a steady speed (lock-up ON) of about 58 km/h (36 mph).
- Lightly depress the accelerator pedal and check that the engine RPM does not change abruptly.
If there is a big jump in engine RPM, there is no lock-up.




2. 2 POSITION TEST
Shift into the 2 position and, while driving with the accelerator pedal held constantly at the full throttle valve opening position, push in one of the pattern selectors and check on the following points:
- Check up-shift operation: check to see that the 1 - 2 up-shift takes place and that the shift point conforms to the automatic shift schedule.

HINT: There is no O/D up-shift and lock-up in the 2 position.




- Check engine braking: while running in the 2 position and 2nd gear, release the accelerator pedal and check the engine braking effect.




- Check for abnormal noises during acceleration and deceleration, and for shock during up-shift and down-shift.

3. L POSITION TEST
Shift into the L position and while driving with the accelerator pedal held constantly at the full throttle valve opening position, push in one of the pattern selectors and check the following points:




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




- Check engine braking: while running in the L position, release the accelerator pedal and check the engine braking effect.




- Check for abnormal noise during acceleration and deceleration.




4. R POSITION TEST
Shift into the R position and while starting at full throttle, check for slipping.




5. P POSITION TEST
Stop the vehicle on a gradient (more than 50) and after shifting into the P position, release the parking brake. Then check to see that the parking lock pawl holds the vehicle in place.

AUTOMATIC SHIFT SCHEDULE




SHIFT POINT




LOCKUP POINT

HINT:
- There is no lock-up in the 2 and L positions.
- In the following cases, the lock-up will be released regardless of the lock-up pattern.
- When the throttle valve is completely closed.
- When the brake light switch is ON.
- Shift-up to 3rd will not occur when the engine coolant temp. is below 35°C (95°F) and the vehicle speed is below 40 km/h (25 mph).
- Shift-up to O/D will not occur when the engine coolant temp. is below 60°C (140°F) and the vehicle speed is below 60 km/h (37 mph).
- During cruise control operation, the shift pattern is fixed in NORM. And when the vehicle speed drops to 10km/h (6 mph) or more below the cruise control set vehicle speed, shift-down from O/D to 3rd occurs.
- The kick-down foot switch turns ON when the accelerator pedal is depressed further with the throttle valve already fully open.