Toyota RM787U, Руководство по обслуживанию и ремонту

Страница: 438 / 1976

- DIAGNOSTICS AUTOMATIC TRANSAXLE
DI-165
319
Author: Date:
2001 SIENNA (RM787U)
6. MECHANICAL SYSTEM TESTS
(a) Measure the stall speed.
The object of this test is to check the overall performance of the transaxle and engine by measuring
the stall speeds in the D position.
NOTICE:
Do the test at normal operating fluid temperature 50 - 80
°
C (122 - 176
°
F).
Do not continuously run this test longer than 5 seconds.
To ensure safety, conduct this test in a wide, clear level area which provides good traction.
The stall test should always be carried out in pairs. One technician should observe the condi-
tions of wheels or wheel stoppers outside the vehicle while the other is doing the test.
(1)
Check the 4 wheels.
(2) Connect an OBD II scan tool or TOYOTA hand-held tester to DLC3.
(3) Fully apply the parking brake.
(4) Keep your left foot pressing firmly on the brake pedal.
(5) Start the engine.
(6) Shift into the D position. Press all the way down on the accelerator pedal with your right foot.
Quickly read the stall speed at this time.
Stall speed: 2,350 - 2,800 rpm
Evaluation:
Problem Possible cause
(a) Stall speed low in D position
Engine output may be insufficient
Stator one-way clutch is operating properly
HINT: If more than 600 rpm below the specified value, the torque
converter clutch could be faulty.
(b) Stall speed high in D position
Line pressure too low
Forward clutch slipping
No.2 one-way clutch not operating properly
O/D clutch slipping
Improper fluid level
O/D one-way clutch not operating properly
(b) Measure the time lag.
When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before
the shock can be felt. This is used for checking the conditions of the O/D direct clutch, forward clutch,
and 1st & reverse brake.
NOTICE:
Do the test at normal operating fluid temperature 50 - 80
°
C (122 - 176
°
F).
Be sure to allow 1 minute interval between tests.
Take 3 measurements and take the average value.
(1)
Connect an OBD II scan tool or TOYOTA hand-held tester to DLC3.
(2) Fully apply the parking brake.
(3) Start the engine and check idle speed.
Idle speed: 700
±
50 rpm (In N position and air conditioner OFF)
(4) Shift the shift lever from N to D position. Using a stop watch, measure the time from when the
lever is shifted until the shock is felt.
Time lag: N
→
D Less than 1.2 seconds
(5) In the same manner, measure the time lag for N
→
R.
Time lag: N
→
R Less than 1.5 seconds