engine TOYOTA SIENNA 2007 Service Repair Manual

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–13
AX
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
AX
(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
AX
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)

AX–16U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
(9) Disconnect the connector of the transmission
wire.
HINT:
Disconnect the connector only when performing
the D position stall test.
(10)Start the engine.
(11)Firmly depress the brake pedal, shift to the D
position, depress the accelerator pedal all the
way down and check the line pressure while the
stall test is performed.
Specified line pressure:
(12)Turn the ignition switch off.
(13)Remove the SST, install the test plug A.
(14)Remove the test plug B, install the SST and
start engine.
SST 09992-00095 (09992-00231, 09992-
00271)
(15)Connect the transmission wire connector,
depress the brake pedal firmly, shift to the R
position and check that the line pressure while
the engine is idling and during the stall test.
Specified line pressure:
(16)Remove the SST, install the test plug B.
(17)Clear the DTC.
Evaluation:
C160154E01
Condition
D position kPa (kgf / cm2, psi)
Stall test931 to 1,031 kPa
(9.5 to 10.5 kgf/cm
2, 135 to 150 psi)
Condition
R position kPa (kgf / cm
2, psi)
Idling672 to 742 kPa
(6.9 to 7.6 kgf/cm
2, 97 to 108 psi)
Stall test1,768 to 1,968 kPa
(18.0 to 20.1 kgf/cm
2, 256 to 285 psi)
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
• U/D (Underdrive) direct clutch defective
Pressure is low in the D position only• D position circuit fluid leak
• Forward clutch defective
Pressure is low in the R position only• R position circuit fluid leak
• Reverse clutch defective
• 1st and reverse brake defective

AX–18U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
INITIALIZATION
1. RESET MEMORY
NOTICE:
• Perform the RESET MEMORY (AT initialization)
when replacing the automatic transaxle assembly,
engine assembly or ECM.
• The RESET MEMORY can be performed only with
the Intelligent tester.
HINT:
The ECM memorizes the condition that the ECT controls
the automatic transaxle assembly and engine assembly
according to those characteristics. Therefore, when the
automatic transaxle assembly, engine assembly, or ECM
has been replaced, it is necessary to reset the memory
so that the ECM can memorize the new information.
Reset procedure is as follows.
(a) Turn the engine switch off.
(b) Connect the intelligent tester together with the CAN
VIM (controller area network vehicle interface
module) to the DLC3.
(c) Turn the ignition switch to the ON position and push
the intelligent tester main switch on.
(d) Select the item "DIAGNOSIS / ENHANCED OBD
II".
(e) Perform the reset memory procedure from the
ENGINE menu.
CAUTION:
After performing the RESET MEMORY, be sure
to perform the ROAD TEST (See page AX-9)
described earlier.
HINT:
The ECM is learned by performing the ROAD TEST.
(1) Tester menu flow:

AX–20U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
MONITOR DRIVE PATTERN
1. MONITOR DRIVE PATTERN FOR ECT TEST
(a) Perform this drive pattern as one method to
simulate the detection conditions of the ECT
malfunctions. (The DTCs may not be detected due
the actual driving conditions. And some codes may
not be detected through this drive pattern.)
HINT:
Preparation for driving
• Warm up the engine sufficiently. (Engine coolant
temperature is 60
C (140F) or higher)
• Drive the vehicle when the atmospheric
temperature is -10
C (14F) or higher.
(Malfunction is not detected when the
atmospheric temperature is less than -10
C
(14
F))
Driving note
• Drive the vehicle through all gears.
Stop
1st 2nd 3rd 4th 5th 5th
(lock-up ON).
• Repeat the above driving pattern three times or
more.
NOTICE:
• The monitor status can be checked using the
OBD II scan tool or intelligent tester. When
using the intelligent tester, monitor status
can be found in the "ENHANCED OBD II /
DATA LIST" or under "CARB OBD II".
• In the event that the drive pattern must be
interrupted (possibly due to traffic conditions
or other factors), the drive pattern can be
resumed and, in most cases, the monitor can
be completed.
• Perform this drive pattern on a level road as
much as possible and strictly observe the
posted speed limits and traffic laws while
driving.

AX–22U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
PROBLEM SYMPTOMS TABLE
HINT:
• If a normal code is displayed during the diagnostic trouble
code check although the trouble still occurs, check the
electrical circuits for each symptom in the order given in
the charts on the following pages and proceed to the page
given for troubleshooting.
• The Matrix Chart is divided into 2 chapters.
• When the circuit on which mark *1 is attached is a
malfunction, DTC could be output.
Refer to the table below when the trouble cause is considered
to be electrical. If the instruction PROCEED TO NEXT
CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE is given in the flowchart of each circuit, inspect the
suspected areas in descending order for each symptom. If
the trouble still occurs even though there are no
abnormalities in the inspections listed for the symptoms,
check and replace the ECM.
1. Chapter 1: Electronic Circuit Matrix Chart
Symptom Suspected Area See page
No down-shift (A particular gear, from 1st to 4th gear,
is not down-shifted)ECMIN-30
No down-shift (5th -> 4th)Transmission control switch (D <--> 4 position) circuitAX-38
Shift solenoid valve S4 circuit *1AX-104
ECMIN-30
No up-shift (A particular gear, from 1st to 4th gear, is
not up-shifted)ECMIN-30
No up-shift (4th -> 5th)Transmission control switch (D <--> 4 position) circuitAX-38
Shift solenoid valve S4 circuit *1AX-104
ECMIN-30
No lock-upStop light switch circuit *1AX-56
Engine coolant temp. sensor circuit *1ES-56
ECMIN-30
No lock-up off ECMIN-30
Shift point too high or too lowThrottle position sensor circuit *1ES-56
ECMIN-30
Up-shift to 5th from 4th while shift lever is in 4 positionTransmission control switch (D <--> 4 position) circuitAX-38
ECMIN-30
Up-shift to 5th from 4th while engine is coldEngine coolant temp. sensor circuit *1ES-56
ECMIN-30
Up-shift to 2nd from 1st while shift lever is in L positionTransmission control switch (L <--> 2 position) circuit *1AX-38
ECMIN-30
Harsh engagement (N -> D)Shift solenoid valve SL1 circuit *1AX-70
ECMIN-30
Harsh engagement (Lock-up) ECMIN-30
Harsh engagement (Any driving position) ECMIN-30
Poor acceleration ECMIN-30
No kick-down ECMIN-30
Engine stalls when starting off or stopping ECMIN-30
Malfunction in shiftingPark/neutral position switch circuit *1AX-38
Transmission control switch (D <--> 4 position) circuitAX-38
ECMIN-30

AX–24U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
Harsh engagement (5th -> 4th)Valve body assemblyAX-136
B3 accumulatorAX-181
Slip or shudder (Forward and reverse: After warm-up)Valve body assemblyAX-136
Oil strainerAX-136
Direct and O/D clutch (C0)AX-181
Forward clutch (C1)AX-181
U/D clutch (C3)AX-181
2nd and brake (B1)AX-181
U/D brake (B3)AX-181
No. 1 one-way clutch (F1)AX-181
U/D one-way clutch (F2)AX-181
Torque converter clutchAX-172
Slip or shudder (Particular position: Just after engine
starts)Torque converter clutchAX-172
Slip or shudder (R position)Reverse clutch (C2)AX-181
1st and reverse brake (B2)AX-181
Slip or shudder (1st)Forward clutch (C1)AX-181
No. 1 one-way clutch (F1)AX-181
U/D one-way clutch (F2)AX-181
Slip or shudder (2nd) 2nd and O/D brake (B1)AX-181
Slip or shudder (3rd) Direct and O/D clutch (C0)AX-181
Slip or shudder (4th) 2nd and O/D brake (B1)AX-181
Slip or shudder (5th) U/D clutch (C3)AX-181
Shift position too high or too low Shift solenoid valve SLTAX-116
No engine braking (1st +- 4th: D position) U/D brake (B3)AX-181
No engine braking (1st: L (1) position)Valve body assemblyAX-136
1st and reverse brake (B2)AX-181
No engine braking (2nd: 2 position)Valve body assemblyAX-136
2nd and O/D brake (B1)AX-181
No engine braking (3rd: 3 position) U/D brake (B3)AX-181
No kick-down Valve body assemblyAX-136
Poor acceleration (All positions)Shift solenoid valve SLTAX-116
Torque converter clutchAX-172
Poor acceleration (5th)U/D clutch (C3)AX-181
U/D planetary gear unitAX-181
Engine stalls when starting off or stoppingShift solenoid valve DSLAX-60
Torque converter clutchAX-172 Symptom Suspected Area See page

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–33
AX
(b) When not using the OBD II scan tool or intelligent
tester: Clearing the DTCs.
(1) Disconnect the battery terminal or remove the
EFI and ETCS fuses from the engine room J/B
for 60 seconds or more. However, if you
disconnect the battery terminal, perform do the
"INITIALIZE" procedure.

AX–34U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
CHECK MODE PROCEDURE
HINT:
Check mode has a higher sensitivity to malfunctions and can
detect malfunction that normal mode cannot detect. Check
mode can also detect all the malfunctions that normal mode
can detect. In check mode, DTCs are detected with 1-trip
detection logic.
1. DTC CHECK (CHECK MODE)
HINT:
Intelligent tester only: Compared to the normal mode, the
check mode is more sensitive for detecting malfunctions.
Furthermore, the same diagnostic items which are
detected in the normal mode can also be detected in the
check mode.
(a) Procedure for Check Mode using the intelligent
tester.
(1) Check the initial conditions.
• Battery positive voltage 11 V or more
• Throttle valve fully closed
• Transaxle in the P or N position
• A/C switch is off
(2) Turn the ignition switch off.
(3) Connect the intelligent tester together with the
CAN VIM (controller area network vehicle
interface module) to the DLC3.
(4) Turn the ignition switch to ON position and turn
the intelligent tester main switch on.
(5) Select the item "DIAGNOSIS/ENHANCED OBD
II/CHECK MODE" (Check that the MIL flashes).
NOTICE:
All DTCs and freeze frame data recorded will
be erased if: 1) the intelligent tester is used
to change the ECM from normal mode to
check mode or vice-versa; or 2) during check
mode, the ignition switch is turned from the
ON to ACC position or turned OFF.
(6) Start the engine (the MIL goes off after the
engine starts).
(7) Perform "MONITOR DRIVE PATTERN" for the
ECT test (See page AX-17). (Or, simulate the
conditions of the malfunction described by the
customer).
NOTICE:
Leave the ignition switch in the ON position
until you have checked the DTCs, etc.
(8) After simulating malfunction conditions, use the
intelligent tester diagnosis selector to check the
DTCs and freeze frame data, etc.
(9) When you use intelligent tester: Select the item
"DIAGNOSIS / ENHANCED OBD II / DTC INFO
/ CURRENT CODES".
(10)After checking the DTC, inspect the applicable
circuit.
C159873E01
BR03904E17