Toyota Celica 2005, Repair Manual

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DI − 774
− DIAGNOSTICS AUTOMATIC TRANSAXLE (U341E)
2005 CELICA (RM1131U)
9. 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 symp-
toms.
10. ROAD TEST
NOTICE:
Perform the test at normal operating ATF temperature 50 to 80
°
C (122 to 176
°
F).
(a) D position test
Shift into the D position and fully depress the accelerator pedal and check the following points.
(1)
Check up − shift operation.
Check that 1
→
2, 2
→
3 and 3
→
O/D up − shifts take place, and that the shift points conform to
the automatic shift schedule (See page SS − 44).
HINT:
S
O/D Gear Up − shift Prohibition Control (1. Coolant temp. is 60
°
C (140
°
F) or less. 2. If there is a 10
km/h (6 mph) difference between the set cruise control speed and vehicle speed.)
S
O/D Gear Lock − up Prohibition Control (1. Brake pedal is depressed. 2. Coolant temp. is 60 ° C (140
°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 up − shifts.
(3) Check for abnormal noises and vibration.
Drive in the D position lock
− up or O/D gear and check for abnormal noises and vibration.
HINT:
The check for the cause of abnormal noises and vibration must be done very thoroughly as it could also be
due to loss of balance in the differential, torque converter clutch, etc.
(4) Check kick − down operation.
While driving in the D position, 2nd, 3rd and O/D gears, check that the possible kick − down ve-
hicle speed limits for 2 → 1, 3 → 2 and O/D → 3 kick − downs conform to those indicated on the
automatic shift schedule (See page SS − 44).
(5) Check abnormal shock and slip at kick − down.
(6) Check the lock − up mechanism.
S
Drive in D position, O/D gear, at a steady speed (lock − up ON) of about 60 km/h (37 mph).
S
Lightly depress the accelerator pedal and check that the engine speed does not change
abruptly.
If there is a big jump in engine speed, there is no lock − up.
(b) 2 position test
Shift into the 2 position and fully depress the accelerator pedal and check 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 (See page SS − 44).
HINT:
There is no O/D up
− shift and lock − up in the 2 position.
(2) Check engine braking.
While driving in the 2 position and 2nd gear, release the accelerator pedal and check the engine
braking effect.
(3) Check for abnormal noises during acceleration and deceleration, and for shock at up − shift and
down − shift.
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