TOYOTA SIENNA 2007 Service Repair Manual

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–7
AX
HOW TO PROCEED WITH
TROUBLESHOOTING
HINT:
• The ECM of this system is connected to the CAN and
multiplex communication system. Therefore, before
starting troubleshooting, make sure to check that there is
no trouble in the CAN and multiplex communication
systems.
• The intelligent tester can be used at steps 3, 4, 6, and 9.
NEXT
NEXT
NEXT
HINT:
(See page AX-27).
NEXT
NEXT
HINT:
(See page AX-28).
NEXT
HINT:
(See page AX-9).
1Vehicle Brought to Workshop
2Customer Problem Analysis
3Connect the OBD II scan tool or intelligent tester to DLC3
4Check and Clear DTCs and Freeze Frame Data
5Visual Inspection
6Setting the Check Mode Diagnosis
7Problem Symptom Confirmation
Symptom does not occur: Go to step 8

AX–8U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
HINT:
(See page IN-35).
NEXT
HINT:
(See page AX-27).
HINT:
(See page AX-127, AX-123 and AX-148).
NG
OK
HINT:
(See page AX-12).
NG
OK
HINT:
(See page AX-14).
NG
OK
HINT:
(See page AX-15).
NGSymptom occurs: Go to step 9
8Symptom Simulation
9DTC Check
DTC is not output: Go to step 10
DTC is output: Go to step 17
10Basic Inspection
Go to step 19
11Mechanical System Test
Go to step 16
12Hydraulic Test
Go to step 16
13Manual Shifting Test
Go to step 15

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–9
AX
OK
HINT:
(See page AX-19).
NG
OK
HINT:
(See page AX-19).
NEXT
HINT:
(See page AX-35).
NEXT
NEXT
NEXT
NEXT
14Problem Symptoms Table Chapter 1
Go to step 18
15Problem Symptoms Table Chapter 2
16Part Inspection
Go to step 19
17DTC Chart
18Circuit Inspection
19Repair or Replace
20Confirmation Test
End

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–7
AX
HOW TO PROCEED WITH
TROUBLESHOOTING
HINT:
• The ECM of this system is connected to the CAN and
multiplex communication system. Therefore, before
starting troubleshooting, make sure to check that there is
no trouble in the CAN and multiplex communication
systems.
• The intelligent tester can be used at steps 3, 4, 6, and 9.
NEXT
NEXT
NEXT
HINT:
(See page AX-27).
NEXT
NEXT
HINT:
(See page AX-28).
NEXT
HINT:
(See page AX-9).
1Vehicle Brought to Workshop
2Customer Problem Analysis
3Connect the OBD II scan tool or intelligent tester to DLC3
4Check and Clear DTCs and Freeze Frame Data
5Visual Inspection
6Setting the Check Mode Diagnosis
7Problem Symptom Confirmation
Symptom does not occur: Go to step 8

AX–8U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
HINT:
(See page IN-35).
NEXT
HINT:
(See page AX-27).
HINT:
(See page AX-127, AX-123 and AX-148).
NG
OK
HINT:
(See page AX-12).
NG
OK
HINT:
(See page AX-14).
NG
OK
HINT:
(See page AX-15).
NGSymptom occurs: Go to step 9
8Symptom Simulation
9DTC Check
DTC is not output: Go to step 10
DTC is output: Go to step 17
10Basic Inspection
Go to step 19
11Mechanical System Test
Go to step 16
12Hydraulic Test
Go to step 16
13Manual Shifting Test
Go to step 15

U151E AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–9
AX
OK
HINT:
(See page AX-19).
NG
OK
HINT:
(See page AX-19).
NEXT
HINT:
(See page AX-35).
NEXT
NEXT
NEXT
NEXT
14Problem Symptoms Table Chapter 1
Go to step 18
15Problem Symptoms Table Chapter 2
16Part Inspection
Go to step 19
17DTC Chart
18Circuit Inspection
19Repair or Replace
20Confirmation Test
End

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
AX
(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
AX
(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.

U151E 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:
2,300 +- 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