Toyota T100 1996, Service Manual, Page: 533 / 2062

− DIAGNOSTICS AUTOMATIC TRANSMISSION
DI − 269
1996 TOYOTA T100 (RM449U)
4. ROAD TEST
NOTICE:
Perform the test at normal operating ATF temperature 50
− 80 ° C (122 − 176 ° F).
(a) D position test
Shift into the D position and fully depress the accelerator pedal and and check the following points:
(1)
Check up − shift operation.
1 → 2, 2 → 3 and 3 → O/D up − shift takes place, at the shift point shown in the automatic shift
schedule (See page SS − 49 ).
HINT:
There is no O/D up
− shift or lock − up when the coolant temperature is below 60 ° C (140 ° F).
Evaluation:
Problem Possible cause
If there is no 1
→
2 up − shift
S Shift solenoid valve No.2 is stuck
S 1 − 2 shift valve is stuck
If there is no 2 → 3 up − shift
S Shift solenoid valve No.1 is stuck
S 2 − 3 shift valve is stuck
If there is no 3 → O/D up − shift S 3 − 4 shift valve is stuck
If the shift point is defective S Throttle valve, 1 − 2 shift valve, 2 − 3 shift valve, etc. are defective
If the lock up is defective
S Shift solenoid valve SL is stuck
S Lock − up relay valve is stuck
(2) Check for shift shock and slip.
Check for shock and slip at the 1
→ 2, 2 → 3 and 3 → O/D up − shifts.
Evaluation:
Problem Possible cause
If the shock is excessive
S Line pressure is too high
S Accumulator is defective
S Check ball is defective
(3) Check for abnormal noises and vibration.
Run at 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 running in the D position, 2nd, 3rd and O/D gears, check to see that the 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 (See page SS − 49 ).
(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).
S
Lightly depress the accelerator pedal and check that there is lock − up.
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 to see that the 1 → 2 up − shift takes place and that the shift point conforms to the automatic
shift schedule (See page SS − 49 ).