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 transaxle does not up-shift, 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: Do the test at normal ATF operating temperature 50-80 °C (122- 176 °F).

(a) D position test
Shift into the D position and keep the accelerator pedal constant at the full throttle valve opening position, and check the following points:
(1) Check up-shift operation.
Check that 1 -> 2, 2 -> 3 and 3 -> O/D upshift takes place, and that the shift points conform to the automatic shift schedule.

HINT:
O/D Gear Upshift Prohibition Control
- Engine coolant temperature is 55 °C (122 °F) or less.
- If there is a 10 km/h (6 mph) difference between the set cruise control speed and vehicle speed.
- O/D main switch is pushed ON (During the O/D OFF indicator light lights up.)
O/D Gear Lock-up Prohibition Control
- Brake pedal is depressed.
- Engine coolant temperature is 55 °C (122 °F) or less.

(2) Check for shift shock and slip.
Check for shock and slip at the 1 -> 2, 2 -> 3 and 3 -> O/D upshifts.
(3) 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 done very thoroughly as it could also be due to loss of balance in the differential and torque converter clutch, etc.

(4) Check kickdown operation.
While running in the D position, 2nd, 3rd and O/D gears, check that the possible kickdown vehicle speed limits for 2 -> 1, 3 -> 2 and O/D -> 3 kick-clowns conform to those indicated in the automatic shift schedule.
(5) Check abnormal shock and slip at kick-clown.
(6) Check the lock-up mechanism.
- Drive in the D position, O/D gear, at a steady speed (lock-up ON) of about 57 km/h (47 mph).
- Lightly depress the accelerator pedal and check that the RPM does not change abruptly. If there is a big jump in RPM, there is no lock-up.
(b) 2 position test
Shift into the 2 position and, while driving with the accelerator pedal held constantly at the full throttle valve opening position, check on 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.

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

(2) Check engine braking.
While running in the 2nd gear of the 2 position, release the accelerator pedal and check the engine braking effect.
(3) Check for abnormal noise during acceleration and deceleration, and for shock during upshift and down-shift.
(c) L position test
Shift into the L position, check that there is no upshift to 2nd gear.
(1) Check no upshift.
While running in the L position, check that there is no upshift to 2nd gear.
(2) Check engine braking.
While running in the L position, release the accelerator pedal and check the engine braking effect.
(3) Check for abnormal noise during acceleration and deceleration.
(d) R position test
Shift into the R position and while starting at full throttle, check for slipping.

CAUTION: Before conducting this test ensure that the test area is free from people and obstruction.

(e) 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 that the parking lock pawl holds the vehicle in place.