2007 TOYOTA SIENNA shock

AX–6U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
SYSTEM DESCRIPTION
1. SYSTEM DESCRIPTION
(a) The ECT (Electronic controlled automatic
transmission/transaxle) is an automatic
transmission/transaxle that electronically controls
shift timing using the ECM. The ECM detects
electrical signals that indicate engine and driving
conditions, and controls the shift point, based on
driver habits and road conditions. As a result, fuel
efficiency and power transmission performance are
improved.
Shift shock has been reduced by controlling the
engine and transmission simultaneously.
In addition, the ECT has features such as follows:
• Diagnostic function.
• Fail-safe function when a malfunction occurs.

AX–10U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
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ROAD TEST
1. PROBLEM SYMPTOM CONFIRMATION
(a) Based on the result of the customer problem
analysis, try to reproduce the symptoms. If the
problem is that the transaxle does not shift up, shift
down, or the shift point is too high or too low,
conduct the following road test referring to the
automatic shift schedule and simulate the problem
symptoms.
2. ROAD TEST
NOTICE:
Perform the test at the ATF temperature 50 to 80
C
(122 to 176
F) in the normal operation.
(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, 3 4 and 4 5th up-
shifts take place, and that the shift points
conform to the automatic shift schedule (See
page SS-24).
HINT:
5th Gear Up-shift Prohibition Control
• Engine coolant temperature is 55
C (131F)
or less and vehicle speed is at 80 km/h (176
mph) or less.
• ATF temperature is -2
C (28F) or less.
4th Gear Up-shift Prohibition Control
• Coolant temperature is 47
C (117F) or less
and vehicle speed is at 55 km/h (34 mph) or
less.
5th and 4th Gear Lock-up Prohibition Control
• Brake pedal is depressed.
• Accelerator pedal is released.
• Coolant temperature is 60
C (140F) or less.
(2) Check for shift shock and slip.
Check for shock and slip at the 1
2, 2 3, 3
4 and 4 5th up-shifts.
(3) Check for abnormal noise and vibration.
Drive in the D position lock-up or 5th gear, and
check for abnormal noises 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, torque converter clutch, etc.
(4) Check kick-down operation.
Check that the possible kick-down vehicle speed
limits for 2nd to 1st, 3rd to 2nd, 4th to 3rd, 5th to
4th kick-downs conform to those indicated on
the automatic shift schedule while driving
through all gears with the shift lever in the D
position (See page SS-24).
(5) Check abnormal shock and slip at kick-down.

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–11
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(6) Check the lock-up mechanism.
• Drive in D position (5th gear), at a steady
speed (lock-up ON).
• Lightly depress the accelerator pedal and
check that the engine speed does not change
abruptly.
HINT:
• There is no lock-up in the 1st and 2nd gear.
• 4th lock-up operates while uphill-downhill
control is active in D position.
• 3rd lock-up operates while uphill-downhill
control is active in D position.
• ATF temperature is 120
C (248F) or more.
• If there is a big jump in engine speed, there is
no lock-up.
(b) 4 (O/D OFF) position test:
Shift into the 4 position and fully depress the
accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1
2, 2 3 and 3 4 up-shift
take place and that the shift point conforms to
the automatic shift schedule (See page SS-24).
HINT:
There is no 5th up-shift in the 4 position.
(2) Check engine braking.
While driving in the 4 position and 4th gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.
(c) 3 position test:
Shift into the 3 position and fully depress the
accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1
2 and 2 3 up-shift take
place and that the shift point conforms to the
automatic shift schedule (See page SS-24).
HINT:
There is no 4th up-shift and lock-up in the 3
position.
(2) Check engine braking.
While running in the 3 position and 3rd gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.

AX–12U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
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(d) 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-24).
HINT:
There is no 3rd up-shift and lock-up in the 2
position.
(2) Check engine braking.
While running in the 2 position and 2nd gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.
(e) L position test:
Shift into the L position and fully depress the
accelerator pedal and check the following points.
(1) Check no up-shift.
While running in the L position, check that there
is no up-shift to 2nd gear.
HINT:
There is no lock-up in the L position.
(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.
(f) R position test:
Shift into the R position and fully depress the
accelerator pedal and check for slipping.
CAUTION:
Before conducting this test ensure that the test
area is free from people and obstruction.
(g) P position test:
Stop the vehicle on the grade (more than 5
) and
after shifting into the P position, release the parking
brake. Then, check that the parking lock pawl holds
the vehicle in place.
(h) Uphill/downhill control function test:
(1) Check that the gear does not up-shift to the 4th
or 5th gear while the vehicle is driving uphill.
(2) Check that the gear automatically down-shifts
from 5th to 4th or from the 4th to 3rd gear when
brake is applied while the vehicle is driving
downhill.

AX–14U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
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(b) Measure the time lag.
(1) 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 clutch and brake.
NOTICE:
• Perform the test at the normal operating
ATF (Automatic Transmission Fluid)
temperature: 50 to 80
C (122 to 176F).
• Be sure to allow 1 minute interval between
tests.
• Perform the test three times, and measure
the time lags. Calculate the average value
of the three time lags.
• When conducting stall test, do not
continue more than 10 seconds.
(2) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(3) Fully apply the parking brake.
(4) Start and warm up the engine and check idle
speed.
Idle speed:
approx. 700 rpm (In N position and A/C
OFF)
(5) Shift the 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
(6) In the same way, measure the time lag for N

R.
Time lag:
N
R less than 1.5 seconds
Evaluation (If N
D or N R time lag is longer than the specified):
Problem Possible cause
N
D time lag is longer• Line pressure is too low
• Forward clutch worn
• No.1 one-way clutch is not operating properly
• U/D (Underdrive) one-way clutch is not operating
• U/D (Underdrive) brake worn
N
R time lag is longer• Line pressure is too low
• Reverse clutch worn
• 1st and reverse brake worn
• U/D (Underdrive) brake worn

AX–10U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
ROAD TEST
1. PROBLEM SYMPTOM CONFIRMATION
(a) Based on the result of the customer problem
analysis, try to reproduce the symptoms. If the
problem is that the transaxle does not shift up, shift
down, or the shift point is too high or too low,
conduct the following road test referring to the
automatic shift schedule and simulate the problem
symptoms.
2. ROAD TEST
NOTICE:
Perform the test at the ATF temperature 50 to 80
C
(122 to 176
F) in the normal operation.
(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, 3 4 and 4 5th up-
shifts take place, and that the shift points
conform to the automatic shift schedule (See
page SS-24).
HINT:
5th Gear Up-shift Prohibition Control
• Engine coolant temperature is 55
C (131F)
or less and vehicle speed is at 80 km/h (176
mph) or less.
• ATF temperature is -2
C (28F) or less.
4th Gear Up-shift Prohibition Control
• Coolant temperature is 47
C (117F) or less
and vehicle speed is at 55 km/h (34 mph) or
less.
5th and 4th Gear Lock-up Prohibition Control
• Brake pedal is depressed.
• Accelerator pedal is released.
• Coolant temperature is 60
C (140F) or less.
(2) Check for shift shock and slip.
Check for shock and slip at the 1
2, 2 3, 3
4 and 4 5th up-shifts.
(3) Check for abnormal noise and vibration.
Drive in the D position lock-up or 5th gear, and
check for abnormal noises 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, torque converter clutch, etc.
(4) Check kick-down operation.
Check that the possible kick-down vehicle speed
limits for 2nd to 1st, 3rd to 2nd, 4th to 3rd, 5th to
4th kick-downs conform to those indicated on
the automatic shift schedule while driving
through all gears with the shift lever in the D
position (See page SS-24).
(5) Check abnormal shock and slip at kick-down.

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–11
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(6) Check the lock-up mechanism.
• Drive in D position (5th gear), at a steady
speed (lock-up ON).
• Lightly depress the accelerator pedal and
check that the engine speed does not change
abruptly.
HINT:
• There is no lock-up in the 1st and 2nd gear.
• 4th lock-up operates while uphill-downhill
control is active in D position.
• 3rd lock-up operates while uphill-downhill
control is active in D position.
• ATF temperature is 120
C (248F) or more.
• If there is a big jump in engine speed, there is
no lock-up.
(b) 4 (O/D OFF) position test:
Shift into the 4 position and fully depress the
accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1
2, 2 3 and 3 4 up-shift
take place and that the shift point conforms to
the automatic shift schedule (See page SS-24).
HINT:
There is no 5th up-shift in the 4 position.
(2) Check engine braking.
While driving in the 4 position and 4th gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.
(c) 3 position test:
Shift into the 3 position and fully depress the
accelerator pedal and check the following points.
(1) Check up-shift operation.
Check that the 1
2 and 2 3 up-shift take
place and that the shift point conforms to the
automatic shift schedule (See page SS-24).
HINT:
There is no 4th up-shift and lock-up in the 3
position.
(2) Check engine braking.
While running in the 3 position and 3rd gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.

AX–12U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
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(d) 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-24).
HINT:
There is no 3rd up-shift and lock-up in the 2
position.
(2) Check engine braking.
While running in the 2 position and 2nd gear,
release the accelerator pedal and check the
engine braking effect.
(3) Check for abnormal noise during acceleration
and deceleration, and for shock at up-shift and
down-shift.
(e) L position test:
Shift into the L position and fully depress the
accelerator pedal and check the following points.
(1) Check no up-shift.
While running in the L position, check that there
is no up-shift to 2nd gear.
HINT:
There is no lock-up in the L position.
(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.
(f) R position test:
Shift into the R position and fully depress the
accelerator pedal and check for slipping.
CAUTION:
Before conducting this test ensure that the test
area is free from people and obstruction.
(g) P position test:
Stop the vehicle on the grade (more than 5
) and
after shifting into the P position, release the parking
brake. Then, check that the parking lock pawl holds
the vehicle in place.
(h) Uphill/downhill control function test:
(1) Check that the gear does not up-shift to the 4th
or 5th gear while the vehicle is driving uphill.
(2) Check that the gear automatically down-shifts
from 5th to 4th or from the 4th to 3rd gear when
brake is applied while the vehicle is driving
downhill.