Toyota Sequoia (2005). Manual — part 186
–
DIAGNOSTICS
AUTOMATIC TRANSMISSION
DI–539
733
(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 condition of the direct clutch, forward clutch, and
1st and reverse brake.
NOTICE:
Perform the test at the normal operating ATF (Automatic Transmission Fluid) temperature: 50
to 80
°
C (122 to 176
°
F).
Be sure to allow for a 1 minute interval between tests.
Perform the test three times, and measure the time lags. Calculate the average value of the three
time lags.
(1)
Connect a hand–held tester to DLC3.
(2)
Fully apply the parking brake.
(3)
Start and warm up the engine and check idle speed.
Idle speed: approx. 700 rpm (In N position and A/C OFF)
(4)
Shift the lever from the 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
Evaluation (If N
→
D time or N
→
R time lag is longer than the specified):
Problem
Possible cause
N
→
D time lag is longer than specified
Line pressure is too low
Clutch No.1 (C
1
) worn
One–way clutch No.3 (F
3
) is not operating properly
N
→
R time lag is longer than specified
Line pressure is too low
Clutch No.3 (C
3
) worn
Brake No.4 (B
4
) worn
One–way clutch No.1 (F
1
) is not operating properly
DIDIS–01
D14143
SST
SST
DI–540
–
DIAGNOSTICS
AUTOMATIC TRANSMISSION
734
HYDRAULIC TEST
1.
PERFORM HYDRAULIC TEST
Measure the line pressure.
NOTICE:
Perform the test at the normal operating ATF (Auto-
matic Transmission Fluid) temperature: 50 to 80
°
C
(122 to 176
°
F).
The line pressure test should always be carried out in
pairs. One technician should observe the conditions
of wheels or wheel stoppers outside the vehicle while
the other is performing the test.
Be careful to prevent SST hose from interfering with
the exhaust pipe.
This check must be conducted after checking and ad-
justing engine.
Perform under condition that A/C is OFF.
When conducting stall test, do not continue more
than 10 seconds.
(1)
Warm up the ATF (Automatic Transmission Fluid).
(2)
Lift the vehicle up.
(3)
Remove the test plug on the transmission case cen-
ter right side and connect SST.
SST
09992–00095 (09992–00231, 09992–00271)
(4)
Fully apply the parking brake and chock the 4
wheels.
(5)
Start the engine and check idling speed.
(6)
Keep your left foot pressing firmly on the brake ped-
al and shift into D position.
(7)
Measure the line pressure when the engine is idling.
(8)
Depress the accelerator pedal all the way down.
Quickly read the highest line pressure when engine
speed reaches stall speed.
(9)
In the same manner, do the test in R position.
–
DIAGNOSTICS
AUTOMATIC TRANSMISSION
DI–541
735
Specified line pressure:
Condition
D position kPa (kgf / cm
2
, psi)
R position kPa (kgf / cm
2
, psi)
Idling
361 to 421 kPa
(3.7 to 4.3 kgf/cm
2
, 52 to 61
psi)
495 to 576 kPa
(5.0 to 5.9 kgf/cm
2
, 72 to 84
psi)
Stall test
1,236 to 1,332 kPa
(12.6 to 13.6 kgf/cm
2
, 179 to 193
psi)
1,229 to 1,349 kPa
(12.5 to 13.8 kgf/cm
2
, 178 to 196
psi)
Evaluation
Problem
Possible cause
Measured values are higher than specified in all positions
Shift solenoid valve (SLT) defective
Regulator valve defective
Measured values are lower than specified in all positions
Shift solenoid valve (SLT) defective
Regulator valve defective
Oil pump defective
Pressure is low in the D position only
D position circuit fluid leak
Clutch No.1 (C
1
) defective
Pressure is low in the R position only
R position circuit fluid leak
Clutch No.3 (C
3
) defective
Brake No.4 (B
4
) defective
DIDIT–01
D11984
DI–542
–
DIAGNOSTICS
AUTOMATIC TRANSMISSION
736
MANUAL SHIFTING TEST
1.
MANUAL SHIFTING TEST
HINT:
With this test, it can be determined whether the trouble oc-
curs in the electrical circuit or is a mechanical problem in
the transmission.
If any abnormalities are found in the following test, the
problem is in the transmission itself.
(a)
Disconnect the connector of the transmission wire.
(b)
Drive with the transmission wire disconnected.
Shifting the shift lever to the L, 2, 3, 4 and D position to
check whether the shifting condition changes the table
below.
Shift Position
Shifting Condition
L
⇔
2
No Shift (Not Change)
2
⇔
3
Down Shift
⇔
Up Shift
3
⇔
4
Down Shift
⇔
Up Shift
4
⇔
D
No Shift (Not Change)
HINT:
When driving with the transmission wire disconnected, the gear
position will be as follows:
When the shift lever is in the L or the 2 position, the gear
is held in the 1st position.
When the shift lever is in the 3rd position, the gear is held
in the 3rd position.
When the shift lever is in the 4 or the D position, the gear
is held in the 4th position.
When the shift lever is in the R or the P position, the gear
is also in the R or the P position respectively.
(c)
Connect the connector of the transmission wire.
(d)
Clear the DTC (See page
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