engine TOYOTA SIENNA 2007 Service Repair Manual

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–117
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SYSTEM DESCRIPTION
The linear solenoid valve (SLT) controls the transmission line pressure for smooth transmission operation
based on signals from the throttle position sensor and the vehicle speed sensor. The ECM adjusts the
duty ratio (*) of the SLT solenoid valve to control hydraulic line pressure coming from the primary regulator
valve. Appropriate line pressure assures smooth shifting with varying engine outputs.
(*): Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For example, if A is the period of
continuity in one cycle, and B is the period of non-continuity, then
Duty Ratio=A/(A+B) x 100(%)
DTC P2714Pressure Control Solenoid "D" Performance
(Shift Solenoid Valve SLT)
DTC No. DTC Detection Condition Trouble Area
P2714ECM detects a malfunction on SLT (ON side) according
to the revolution difference of the turbine, intermediate
and the output shaft, and also by the oil pressure. (2-
trip detection logic)• Shift solenoid valve SLT remains closed
• Valve body is blocked
• Automatic transaxle (clutch, brake or gear, etc.)
C108924E02

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–123
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DESCRIPTION
The linear solenoid valve (SLT) controls the transmission line pressure for smooth transmission operation
based on signals from the throttle position sensor and the vehicle speed sensor. The ECM adjusts the
duty cycle of the SLT solenoid valve to control hydraulic line pressure coming from the primary regulator
valve. Appropriate line pressure assures smooth shifting with varying engine outputs.
(*): Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, and B is the period of non-continuity, then
Duty Ratio = A/(A + B) x 100(%)
MONITOR DESCRIPTION
When an open or short in the linear solenoid valve (SLT) circuit is detected, the ECM interprets this as a
fault. The ECM will turn on the MIL and store the DTC.
MONITOR STRATEGY
DTC P2716Pressure Control Solenoid "D" Electrical (Shift
Solenoid Valve SLT)
DTC No. DTC Detection Condition Trouble Area
P2716Open or short is detected in shift solenoid valve SLT
circuit for 1 second or more while driving (1-trip
detecting logic).• Open or short in shift solenoid valve SLT circuit
• Shift solenoid valve SLT
•ECM
Related DTCs P2716: Shift solenoid valve SLT/Range check
Required sensors/Components Shift solenoid valve SLT
Frequency of operation Continuous
Duration 1 sec.
MIL operation Immediate
Sequence of operation None
C114295E01

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–127
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DESCRIPTION
The shift solenoid valve DSL is turned "ON" and "OFF" by signals from the ECM in order to control the
hydraulic pressure operation, the lock-up relay valve, which then controls operation of the lock-up clutch.
MONITOR DESCRIPTION
Torque converter lock-up is controlled by the ECM based on engine rpm, engine load, engine
temperature, vehicle speed, transmission temperature, and shift range selection. The ECM determines
the lock-up status of the torque converter by comparing the engine rpm (NE) to the input turbine rpm (NT).
The ECM calculates the actual transmission gear by comparing input turbine rpm (NT) to counter gear
rpm (NC). When conditions are appropriate, the ECM requests "lock-up" by applying control voltage to the
shift solenoid DSL. When the DSL is opened, it applies pressure to the lock-up relay valve and locks the
torque converter clutch. If the ECM detects an open or short in the DSL solenoid circuit, the ECM
interprets this as a fault in the DSL solenoid or circuit. The ECM will turn on the MIL and store the DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P2769: Range check (Low resistance):
P2770: Range check (High resistance):
DTC P2769Torque Converter Clutch Solenoid Circuit Low
(Shift Solenoid Valve DSL)
DTC P2770Torque Converter Clutch Solenoid Circuit High
(Shift Solenoid Valve DSL)
DTC No. DTC Detection Condition Trouble Area
P2769ECM detects short in solenoid valve DSL circuit (0.1
sec.) when solenoid valve DSL is operated (2-trip
detection logic)• Short in shift solenoid valve DSL circuit
• Shift solenoid valve DSL
•ECM
P2770ECM detects open in solenoid valve DSL circuit (0.1
sec.) when solenoid valve DSL is not operated (2-trip
detection logic)• Open in shift solenoid valve DSL circuit
• Shift solenoid valve DSL
•ECM
Related DTCsP2769: Shift solenoid valve DSL/Range check (Low resistance)
P2770: Shift solenoid valve DSL/Range check (High resistance)
Required sensors/Components Shift solenoid valve DSL
Frequency of operation Continuous
Duration 0.064 sec. or more
MIL operation 2 driving cycles
Sequence of operation None
The monitor will run whenever this DTC is not present. None
Shift solenoid valve DSLON
Solenoid current cut status Not cut
Battery voltage8 V or more
Ignition switchON
Sta r t e rOFF
The monitor will run whenever this DTC is not present. None
Shift solenoid valve DSLON
Battery voltage8 V or more
Ignition switchON

AX–10U151F 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-31).
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-31).
(5) Check abnormal shock and slip at kick-down.

U151F 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-31).
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-31).
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–12U151F 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-31).
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.

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE FLUIDAX–123
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AUTOMATIC TRANSAXLE FLUID
ON-VEHICLE INSPECTION
1. CHECK FLUID LEVEL
HINT:
Drive the vehicle so that the engine and transaxle are at
normal operating temperature.
Fluid temperature:
70 to 80
C (158 to 176F)
(a) Park the vehicle on a level surface and set the
parking brake.
(b) With the engine idling and the brake pedal
depressed, move the shift lever to all positions from
P to L and return to the P position.
(c) Take out the dipstick and wipe it clean.
(d) Put the dipstick back all the way.
(e) Take out the dipstick again and check that the fluid
level is within the HOT range.
If the fluid level is below the HOT range, add new
fluid and recheck the fluid level.
If the fluid level exceeds the HOT range, drain the
fluid once, add the proper amount of new fluid and
recheck the fluid level.
If there are leaks, it is necessary to repair or replace
O-rings, FIPGs, oil seals, plugs and/or other parts.
D025120E05

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–13
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MECHANICAL SYSTEM TESTS
1. PERFORM 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:
• Driving test should be done on a paved road
(a nonskid road).
• Perform the test at the normal operating ATF
(Automatic Transmission Fluid) temperature
50 to 80
C (122 to 176F).
• Do not continuously run this test for longer
than 10 seconds.
• To ensure safety, do 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
conditions of wheels or wheel stoppers
outside the vehicle while the other is doing
the test.
(1) Chock the 4 wheels.
(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) Keep your left foot pressed 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.
(7) Quickly read the stall speed at this time.
Stall speed:
2,600 +- 150 rpm
Evaluation:
Problem Possible cause
(a) Stall engine speed is low in D position• Engine power output may be insufficient
• Stator one-way clutch not operating properly
HINT:
If the value is less than the specified value by 600 rpm or more, the
torque converter could be faulty.
(b) Stall engine speed is high in D position• Line pressure is too low
• Forward clutch slipping
• U/D (Underdrive) brake slipping
• U/D (Underdrive) one-way clutch is not operating properly
• No.1 one-way clutch not operating properly
• Improper fluid level

AX–14U151F 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

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–15
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HYDRAULIC TEST
1. PERFORM HYDRAULIC TEST
(a) Measure the line pressure.
NOTICE:
• Perform the test at the normal operating ATF
(Automatic Transmission Fluid) temperature:
50 to 80
C (122 to 176F).
• 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 adjusting 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 engine under cover.
(4) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(5) Remove the test plug A on the transaxle case
front left side and install the SST.
SST 09992-00095 (09992-00231, 09992-
00271)
NOTICE:
There is a difference in installation point
between D position and R position.
(6) Start the engine.
(7) Using intelligent tester, shift to D position and
hold 3rd gear by active test, and measure the
line pressure in idling.
Specified line pressure:
(8) Turn the ignition switch off.
C160153E01
Condition
D position kPa (kgf / cm2, psi)
Idling372 to 412 kPa
(3.8 to 4.2 kgf/cm
2, 54 to 60 psi)