TOYOTA SIENNA 2007 Service Repair Manual

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–59
AX
DESCRIPTION
This sensor detects the rotation speed of the input turbine. By comparing the input turbine speed signal
(NT) with the counter gear speed sensor signal (NC), the ECM detects the shift timing of the gears and
appropriately controls the engine torque and hydraulic pressure according to various conditions. Thus,
providing smooth gear shift.
Reference (Using an oscilloscope):
Check the waveform between terminals NT+ and NT- of the ECM connector.
Standard: Refer to the illustration.
MONITOR DESCRIPTION
The NT terminal of the ECM detects a revolution signal from the speed sensor (NT) (input RPM). The
ECM calculates a gearshift comparing the speed sensor (NT) with the speed sensor (NC).
While the vehicle is operating in 2nd, 3rd, 4th or 5th gear in the shift position of D, if the input shaft
revolution is less than 300 rpm
*1although the output shaft revolution is more than 1,000 rpm *2, the ECM
detects the trouble, illuminates the MIL and stores the DTC.
*1: Pulse is not output or is irregularly output.
*2: The vehicle speed is 50 km/h (31 mph) or more.
MONITOR STRATEGY
DTC P0717 Turbine Speed Sensor Circuit No Signal
DTC No. DTC Detection Condition Trouble Area
P0717ECM detects conditions (a), (b) and (c) continuously for
5 sec. or more: (1-trip detection logic)
(a) Vehicle speed: 50 km/h (31 mph) or more
(b) Park/neutral position switch (NSW (STAR) and R) is
OFF
(c) Speed sensor (NT): less than 300 rpm• Open or short in transmission revolution sensor NT
(speed sensor NT) circuit
• Transmission revolution sensor NT (speed sensor
NT)
•ECM
• Automatic transaxle assembly
Te r m i n a l N T + - N T -
Tool setting 5 V/DIV., 0.5 ms./DIV.
Vehicle condition Vehicle speed 20 km/h (12 mph)
Related DTCs P0717: Speed sensor (NT)/Verify pulse input
Required sensors/Components Speed sensor (NT), Speed sensor (NC)
Frequency of operation Continuous
Duration 5 sec.
MIL operation Immediate
Sequence of operation None
C053419E13

AX–60U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
COMPONENT OPERATING RANGE
WIRING DIAGRAM
The monitor will run whenever this DTC is not present.P0500 (VSS)
P0748, P0778, P0798 (Shift solenoid valve (range))
Shift change Shift change is completed and before starting next shift change operation
ECM selected gear3rd, 4th
Output shaft rpm1,000 rpm or more
NSW (STAR) switchOFF
R switchOFF
L switchOFF
EngineRunning
Ignition switchON
StarterOFF
Sensor signal rpmLess than 300 rpm
Speed sensor (NT) Turbine speed is equal to engine speed with lock-up ON
G031763E74

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–61
AX
INSPECTION PROCEDURE
(a) Check the speed sensor installation.
OK:
The installation bolt is tightened properly and there
is no clearance between the sensor and transaxle
case.
NG
OK
(a) Disconnect the speed sensor connector from the
transaxle.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(a) Connect the speed sensor connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the
table below.
Standard resistance
(d) Measure the resistance according to the value(s) in the
table below.
1INSPECT SPEED SENSOR INSTALLATION
BR03795E36
REPLACE SPEED SENSOR (NT)
2INSPECT SPEED SENSOR (NT)
C110343E05
Tester ConnectionSpecified Condition
20 C (68 F)
1 - 2 560 to 680
REPLACE SPEED SENSOR (NT)
3CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM)
C160512E01
Tester ConnectionSpecified Condition
20C (68F)
E10-35 (NT+) - E10-27 (NT-) 560 to 680

AX–62U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
Standard resistance (Check for short)
NG
OK
Tester Connection Specified Condition
E10-35 (NT+) - Body ground
10 k
or higher
E10-27 (NT-) - Body ground
REPAIR OR REPLACE HARNESS OR
CONNECTOR
REPLACE ECM

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–63
AX
DESCRIPTION
The purpose of this circuit is to prevent the engine from stalling while driving in lock-up condition when
brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signals to the ECM. Then the ECM cancels the
operation of the lock-up clutch while braking is in progress.
MONITOR DESCRIPTION
This DTC indicates that the stop light switch remains on. When the stop light switch remains ON during
"stop and go" driving, the ECM interprets this as a fault in the stop light switch and the MIL comes on and
the ECM stores the DTC. The vehicle must stop (less than 3 km/h (2 mph)) and go (30 km/h (19 mph) or
more) 5 times for two driving cycles in order to detect a malfunction.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
DTC P0724 Brake Switch "B" Circuit High
DTC No. DTC Detection Condition Trouble Area
P0724The stop light switch remains ON even when the
vehicle is driven in a STOP (less than 3 km/h (2 mph)
and GO (30 km/h (19 mph) or more) fashion 5 times. (2-
trip detection logic).• Short in stop light switch circuit
• Stop light switch
•ECM
Related DTCs P0724: Stop light switch/Rationality
Required sensors/Components Stop light switch, Vehicle speed sensor
Frequency of operation Continuous
Duration GO and STOP 5 times
MIL operation 2 driving cycles
Sequence of operation None
The monitor will run whenever this DTC is not present. None
Ignition switchON
Sta r t e rOFF
Battery voltage8 V or more
GO (Vehicle speed is 30 km/h (18.63 mph) or more) Once
STOP (Vehicle speed is less than 3 km/h (1.86 mph)) Once
Brake switch Remain ON during GO and STOP 5 times

AX–64U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Using the intelligent tester to read the DATA LIST allows the
values or states of switches, sensors, actuators and other
items to be read without removing any parts. This non-
intrusive inspection can be very useful because intermittent
conditions or signals may be discovered before parts or
wiring is disturbed. Reading the DATA LIST information early
in troubleshooting is one way to save diagnostic time.
(a) Warm up the engine.
(b) Turn the ignition switch off.
(c) Connect the OBD II scan tool or intelligent tester
together with the CAN VIM (controller area network
vehicle interface module) to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Turn on the tester.
(f) Select the item "DIAGNOSIS / ENHANCED OBD II /
DATA LIST".
1READ VALUE OF DATA LIST
C160582E01

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–65
AX
(g) According to the display on the tester, read the "DATA
LIST".
NOTICE:
In the table below, the value listed under "Normal
Condition" are reference values. Do not depend
solely on these reference values when deciding
whether apart is faulty or not.
Result
B
A
(a) Remove the stop light switch assembly.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(a) Install the stop light switch assembly.
(b) Measure the voltage according to the value(s) in the
table below when the brake pedal is depressed and
released.
Standard voltage
NG
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
STOP LIGHT SWStop light switch Status/
ON or OFF• Brake Pedal is depressed:
ON
• Brake Pedal is released: OFF-
Result Proceed to
NG A
OK B
Go to step 3
2INSPECT STOP LIGHT SWITCH ASSEMBLY
E065594E39
Switch position Tester Connection Specified Condition
Switch pin free 1 - 2 Below 1
Switch pin pushed in10 k or higher
Switch pin free 3 - 4 10 k
or higher
Switch pin pushed in
Below 1
REPLACE STOP LIGHT SWITCH ASSEMBLY
3CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM)
G035619E25
Condition Tester Connection Specified Condition
Brake pedal is
depressedE4-15 (STP) - Body
ground11 to 14 V
Brake pedal is released Below 1 V
REPAIR OR REPLACE HARNESS OR
CONNECTOR

AX–66U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
OK
REPLACE ECM

U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEMAX–67
AX
SYSTEM DESCRIPTION
The ECM uses the signals from the throttle position sensor, air-flow meter, turbine (input) speed sensor,
intermediate (counter) shaft speed sensor and crankshaft position sensor to monitor the engagement
condition of the lock-up clutch.
Then the ECM compares the engagement condition of the lock-up clutch with the lock-up schedule in the
ECM memory to detect a mechanical problems of the shift solenoid valve DSL, valve body and torque
converter clutch.
MONITOR DESCRIPTION
Torque converter lock-up is controlled by the ECM based on the speed sensor (NT), speed sensor (NC),
engine rpm, engine load, engine temperature, vehicle speed, transmission temperature, and gear
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 turned on, it applies pressure to the
lock-up relay valve and locks the torque converter clutch.
If the ECM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not
requested, the ECM interprets this as a fault in the shift solenoid valve DSL or lock-up system
performance. The ECM will turn on the MIL and store the DTC.
HINT:
Example:
When any of the following is met, the system judges it as a malfunction.
• There is a difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock-up.
(Engine speed is at least 100 rpm greater than input turbine speed.)
• There is no difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock-up off.
(The difference between engine speed and input turbine speed is less than 35 rpm.)
MONITOR STRATEGY
DTC P0741Torque Converter Clutch Solenoid Performance
(Shift Solenoid Valve DSL)
DTC No. DTC Detection Condition Trouble Area
P0741Lock-up does not occur when driving in the lock-up
range (normal driving at 80 km/h [50 mph]), or lock up
remains ON in the lock-up OFF range.
(2-trip detection logic)• Shift solenoid valve DSL remains open or closed
• Valve body is blocked
• Torque converter clutch
• Automatic transaxle (clutch, brake or gear etc.)
• Line pressure is too low
Related DTCsP0741:
Shift solenoid valve DSL/OFF malfunction
Shift solenoid valve DSL/ON malfunction
Required sensors/ComponentsShift solenoid valve DSL, Speed sensor (NT), Speed sensor (NC),
Crankshaft position sensor (NE), Throttle position sensor (VPA1),
Mass air flow sensor (MAF), Transmission temperature sensor
(THO1), Engine coolant temperature sensor (ECT)
Frequency of operation Continuous
DurationOFF malfunction (A)
Continuous.
OFF malfunction (B)
1 sec.
OFF malfunction (C)
3.5 sec.
ON malfunction
1.8 sec.

AX–68U151F AUTOMATIC TRANSAXLE – AUTOMATIC TRANSAXLE SYSTEM
AX
TYPICAL ENABLING CONDITIONS
All:
OFF malfunction (A):
OFF malfunction (B):
OFF malfunction (C):
ON malfunction:
TYPICAL MALFUNCTION THRESHOLDS
Either of the following conditions is met: OFF malfunction or ON malfunction OFF malfunction:
ON malfunction:
MIL operation 2 driving cycles
Sequence of operation None
The monitor will run whenever this DTC is not present.P0115 - P0118 (ECT sensor)
P0125 (Insufficient ECT for closed loop)
P0500 (VSS)
P0748, P0778, P0798 (Shift solenoid valve (range))
ECT (Engine coolant temperature) 10
C (50F) or more
Transmission range"D"
TFT (Transmission fluid temperature) -20
C (-4F) or more
TFT sensor circuitNot circuit malfunction
ECT sensor circuitNot circuit malfunction
Turbine speed sensor circuit Not circuit malfunction
Intermediate shaft speed sensor circuit Not circuit malfunction
Output speed sensor circuit Not circuit malfunction
Shift solenoid valve SL1 circuit Not circuit malfunction
Shift solenoid valve SL2 circuit Not circuit malfunction
Shift solenoid valve SL3 circuit Not circuit malfunction
Shift solenoid valve S4 circuit Not circuit malfunction
Shift solenoid valve SR circuit Not circuit malfunction
Shift solenoid valve DSL circuit Not circuit malfunction
Electronic throttle systemNot circuit malfunction
ECM selected gear3rd
Throttle valve opening angle4.5% or more at engine speed gear 1,900 rpm (varies with engine
speed)
ECM selected gear5th
Vehicle speed10 km/h (6.2 mph) or more
ECM lock-up commandON
ECM selected gear3rd, 4th or 5th
Vehicle speed25 km/h (15.5 mph) or more
ECM lock-up commandOFF
ECM selected gear3rd, 4th or 5th
Throttle valve opening angle7% or more
Vehicle speed25 to 60 km/h (15.5 to 37.3 mph)
Engine Speed - Input (turbine) speed 100 rpm or more
Difference between engine speed and input (turbine) speed Less than 35 rpm