sensor TOYOTA SIENNA 2007 Service Repair Manual

TW–16TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
SYSTEM DESCRIPTION
1. DESCRIPTION OF SYSTEM
(a) A tire pressure warning valve and transmitter is
equipped with a tire pressure sensor and a
transmitter and is installed in a tire wheel assembly.
The sensor measures the tire pressure. The
measured value and transmitter ID are transmitted
to the tire pressure warning antenna and receiver on
the body as radio waves and then sent to the tire
pressure warning ECU from the tire pressure
warning antenna and receiver. If the transmitter ID
has already been registered, the ECU compares the
measured air pressure value with the specified
value. When the value is less than the specified
value registered in the tire pressure warning ECU,
the warning light on the combination meter comes
on.
• The tire pressure warning reset switch addresses
the differences in the standard pressure of the
tire.
2. INITIAL CHECK
(a) The tire pressure warning light turns on for 3
seconds after the ignition switch ON and then goes
off.
HINT:
If the warning light does not turn on for 3 seconds,
troubleshoot the tire pressure warning light circuit.
C159181E01
C124985E04
Trouble Area See procedure
Tire pressure warning light circuitTW-74

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–17
TW
3. WHEN TIRE PRESSURE WARNING LIGHT IS LIT
(a) When the tire pressure warning light does not go off,
or when it comes on during driving, check tire
pressure. If the tire pressure warning light comes on
within several hours after adjusting the tire
pressure, the tire may have a slow air leak.
(b) Under the following conditions, the system may not
function properly.
• Facilities or devices that use similar radio
frequencies are located in the vicinity of the
vehicle.
• A radio device of similar frequency is used in the
vehicle.
• A large amount of snow or ice is stuck to the
vehicle, especially onto the wheels and around
the wheel houses.
• The ID of the tire pressure warning valve and
transmitter has not been registered with the
ECU.
• A film or window tint that may interfere with radio
waves is attached on the glass.
• The battery of the sensor has been depleted.
• The tires without tire pressure warning valve and
transmitter are used.
• Tire chains are used.
• The use of non-genuine wheels may result in the
system failure or air-leak.
• Depending on the tire type, the system may not
function properly even though the specified
wheels are used.
(c) After removing and installing the ECU or a sensor,
check for a diagnostic trouble code and verify that it
is a normal code.
4. FUNCTION OF COMPONENTS
5. TIRE PRESSURE WARNING RESET SWITCH
• By operating the tire pressure warning reset switch,
the tire pressure warning ECU can be set to issue a
warning at an inflation pressure that corresponds to
the standard pressure of tires.
Therefore, the dealer must set the warning threshold
to the proper value in order to comply with the local
regulations.
Components Function
Tire pressure warning valve and transmitterCombined as a single unit with a disc wheel air valve, it measures tire pressure and
temperature and transmits an ID number for measurement value and identification.
Built-in the battery.
Tire pressure warning antenna and receiverReceives and transmits a necessary signal from the transmitter to the tire pressure
warning ECU.
Tire pressure warning ECUReceives a signal from the receiver and identifies it as vehicle's own signal. If the
measured value is equal to or lower than the specified value, it transmits a signal so
that the tire pressure warning light on the combination meter comes on.
Tire pressure warning lightLocated in the combination meter, it informs the driver of lowered tire air pressure
and system failure.
Tire pressure warning reset switch Enters the initialization mode for the change of the standard pressure

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–41
TW
C2166/66 Abnormal Temperature Inside ID2
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2167/67 Abnormal Temperature Inside ID3
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2168/68 Abnormal Temperature Inside ID4
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2171/71 Transmitter ID not Registered Tire pressure warning ECUTW-58
C2176/76 Receiver Error 1. Tire pressure warning antenna
and receiver
2. Wire harness or connector
3. Tire pressure warning ECUTW-60
C2177/77 Initialization not Completed 1. Tire pressure warning valve
and transmitter
2. Tire pressure warning ECU
3. Tire pressure warning antenna
and receiver
4. Wire harness or connectorTW-63
C2181/81 Transmitter ID1 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2182/82 Transmitter ID2 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2183/83 Transmitter ID3 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2184/84 Transmitter ID4 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2191/91 Vehicle Speed Signal Error (Test
Mode DTC)1. Vehicle speed sensor
2. Tire pressure warning ECU
3. Combination meter
4. Wire harness or connectorTW-70 DTC Code Detection Item Trouble Area See page

TW–30TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
(2) Check the tire pressure warning indicator light.
(i) Result
HINT:
After the signal check is completed, check for a
signal check DTC to confirm the system status.
(j) End of SIGNAL CHECK
After completing the test mode (SIGNAL CHECK),
turn the ignition switch off and disconnect the tester.
DTC of SIGNAL CHECK (TEST DIAGNOSIS)
function:
If a trouble code is displayed during the test mode
DTC check, check the circuit listed for that code. For
details of each code, refer to the relevant page listed
under respective "DTC No." in the chart.
Test Signal Normal Condition
Tire Pressure Warning Reset Switch• Switch ON: TPWS indicator comes on
• Switch OFF: TPWS indicator blinks at 0.125
Condition Procedure
SIGNAL CHECK DTC is output Repair the faulty part and enter SIGNAL CHECK again
SIGNAL CHECK DTCs are cleared No problem
DTC No. Detection Item Trouble Area See procedure
C2181/81 Transmitter ID1 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2182/82 Transmitter ID2 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2183/83 Transmitter ID3 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2184/84 Transmitter ID4 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2191/91 Vehicle speed signal error• Vehicle speed sensor
• Combination meter assembly
• Wire harness or connector
• Tire pressure warning ECUTW-70

TW–38TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
Using the intelligent tester to read the DATA LIST allows
the values or states of switches, sensor, 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.
NOTICE:
In the table below, the values listed under "Normal
Condition" are reference values. Do not depend
solely on these reference values when deciding
whether a part is faulty or not.
(a) Make sure that the ignition switch is off.
(b) Connect the intelligent tester to DLC3.
(c) Turn the ignition switch to the ON position.
(d) Following the display on the intelligent tester, read
"DATA LIST".
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
MODE STATUSTire pressure warning system mode/NORMAL
or REG 2nd or REG M or TESTNORMAL: Normal mode
TEST: Test mode-
MAIN TIRENumber of main tire ID to be registered/0, 1, 2,
3, 40 to 4 should be displayed -
VEHICLE SPDVehicle speed reading/min.: 0 km/h (0 mph),
max.: 255 km/h (158 mph)Actual vehicle speedSpeed indicated on the
combination meter
REGIT ID1 CODE
Registered ID1 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID1 is displayed-
REGIT ID2 CODE
Registered ID2 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID2 is displayed-
REGIT ID3 CODE
Registered ID3 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID3 is displayed-
REGIT ID4 CODE
Registered ID4 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID4 is displayed-
TRANS STATUS ID code transmission status/FINISH or NOW FINISH or NOW -
INITIAL SW Tire pressure warning reset switch/ON, OFFON: Switch on
OFF: Switch off-
TIREPRESS1ID1 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm
2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS2ID2 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS3ID3 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS4ID4 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–73
TW
DESCRIPTION
The tire pressure warning ECU receives a speed signal from the combination meter. This DTC is stored
upon entering test mode, and cleared when a vehicle speed signal of 12 mph (20 km/h) is detected for 3
seconds or more. This DTC is output only in test mode.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
• When replacing the tire pressure warning ECU, read the IDs stored in the ECU using the
intelligent tester and write them down before removal.
• It is necessary to perform initialization (See page TW-23) after registration (See page TW-20) of
the transmitter IDs into the tire pressure warning ECU after the ECU has been replaced.
(a) Make sure that the ignition switch is off.
(b) Connect the intelligent tester to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Select the item below in the Data List, and read the value
displayed on the intelligent tester.
DTC C2191/91 Vehicle Speed Signal Error (Test Mode DTC)
DTC No. DTC Detecting Condition Trouble Area
C2191/91 Speed sensor circuit malfunction• Vehicle speed sensor
• Tire pressure warning ECU
• Combination meter
• Wire harness or connector
1READ VALUE ON INTELLIGENT TESTER
E115290E65

TW–30TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
(2) Check the tire pressure warning indicator light.
(i) Result
HINT:
After the signal check is completed, check for a
signal check DTC to confirm the system status.
(j) End of SIGNAL CHECK
After completing the test mode (SIGNAL CHECK),
turn the ignition switch off and disconnect the tester.
DTC of SIGNAL CHECK (TEST DIAGNOSIS)
function:
If a trouble code is displayed during the test mode
DTC check, check the circuit listed for that code. For
details of each code, refer to the relevant page listed
under respective "DTC No." in the chart.
Test Signal Normal Condition
Tire Pressure Warning Reset Switch• Switch ON: TPWS indicator comes on
• Switch OFF: TPWS indicator blinks at 0.125
Condition Procedure
SIGNAL CHECK DTC is output Repair the faulty part and enter SIGNAL CHECK again
SIGNAL CHECK DTCs are cleared No problem
DTC No. Detection Item Trouble Area See procedure
C2181/81 Transmitter ID1 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2182/82 Transmitter ID2 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2183/83 Transmitter ID3 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2184/84 Transmitter ID4 not received• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECUTW-42
C2191/91 Vehicle speed signal error• Vehicle speed sensor
• Combination meter assembly
• Wire harness or connector
• Tire pressure warning ECUTW-70

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–35
TW
3. DIAGNOSIS SYSTEM
(a) DTCs (Normal mode)
(1) DTCs are memorized in the tire pressure
warning ECU and read by the blinks of the tire
pressure warning light or by using the intelligent
tester (See page TW-34).
(b) Test mode
(1) By switching from normal mode into test mode
(input signal check), you can inspect the tire
pressure warning antenna and receiver, each
tire pressure warning valve and transmitter, and
vehicle speed sensor (See page TW-25).
(c) When there is a problem with the tire pressure
warning system, the tire pressure warning light
blinks at 0.5-second intervals, and turns on after 1
minute.
4. CHECK TIRE PRESSURE WARNING LIGHT
(a) Turn the ignition switch to the ON position.
(b) Check that the tire pressure warning light comes on
for 3 seconds.
If the warning check result is not normal, proceed to
the troubleshooting for the tire pressure warning
light circuit.
5. TIRE PRESSURE WARNING LIGHT AND INDICATOR
CHART
HINT:
The table below indicates the state of the tire pressure
warning light and indicator after the ignition switch ON.
C159176E01
Trouble Area See page
Tire pressure warning light circuitTW-74
Immediately
after turning
the ignition
switch ONAlways
Warning light output pattern
Comes on for
3 sec.Goes off Comes on Blinks (*1) Blinks (*2) Blinks (*3) Blinks (*4) Outputs DTC
Normal
--- - - -
Low tire
pressure
--- - - -
System fail
---- - -
Te s t m o d e
------
Initialization
- -----
ECU
connector
poorly
connected---
-- - -
TC ground
(DTC is
output)
- --- - -
TC ground
(DTC is not
output)- --- --

TW–38TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
Using the intelligent tester to read the DATA LIST allows
the values or states of switches, sensor, 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.
NOTICE:
In the table below, the values listed under "Normal
Condition" are reference values. Do not depend
solely on these reference values when deciding
whether a part is faulty or not.
(a) Make sure that the ignition switch is off.
(b) Connect the intelligent tester to DLC3.
(c) Turn the ignition switch to the ON position.
(d) Following the display on the intelligent tester, read
"DATA LIST".
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
MODE STATUSTire pressure warning system mode/NORMAL
or REG 2nd or REG M or TESTNORMAL: Normal mode
TEST: Test mode-
MAIN TIRENumber of main tire ID to be registered/0, 1, 2,
3, 40 to 4 should be displayed -
VEHICLE SPDVehicle speed reading/min.: 0 km/h (0 mph),
max.: 255 km/h (158 mph)Actual vehicle speedSpeed indicated on the
combination meter
REGIT ID1 CODE
Registered ID1 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID1 is displayed-
REGIT ID2 CODE
Registered ID2 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID2 is displayed-
REGIT ID3 CODE
Registered ID3 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID3 is displayed-
REGIT ID4 CODE
Registered ID4 code/min.: 0, max.: FFFFFFF
*1The ID No. registered in the
transmitter ID4 is displayed-
TRANS STATUS ID code transmission status/FINISH or NOW FINISH or NOW -
INITIAL SW Tire pressure warning reset switch/ON, OFFON: Switch on
OFF: Switch off-
TIREPRESS1ID1 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm
2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS2ID2 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS3ID3 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2
TIREPRESS4ID4 tire inflation pressure (Absolute pressure) /
min.: 100 kPa (1 kgf/cm2, 14 psi)
max.: 449.35 kPa (4.5 kgf/cm2, 63 psi)Actual tire inflation pressureIf 100 kPa (1 kgf/cm
2, 14 psi)
for absolute pressure is
displayed, the data has not
been received.
*2

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–41
TW
C2166/66 Abnormal Temperature Inside ID2
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2167/67 Abnormal Temperature Inside ID3
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2168/68 Abnormal Temperature Inside ID4
Tire1. Tires
2. Tire pressure warning valve
and transmitter
3. Tire pressure warning ECUTW-54
C2171/71 Transmitter ID not Registered Tire pressure warning ECUTW-58
C2176/76 Receiver Error 1. Tire pressure warning antenna
and receiver
2. Wire harness or connector
3. Tire pressure warning ECUTW-60
C2177/77 Initialization not Completed 1. Tire pressure warning valve
and transmitter
2. Tire pressure warning ECU
3. Tire pressure warning antenna
and receiver
4. Wire harness or connectorTW-63
C2181/81 Transmitter ID1 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2182/82 Transmitter ID2 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2183/83 Transmitter ID3 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2184/84 Transmitter ID4 not Received
(Test Mode DTC)1. Tire pressure warning valve
and transmitter
2. Tire pressure warning antenna
and receiver
3. Wire harness or connector
4. Tire pressure warning ECUTW-42
C2191/91 Vehicle Speed Signal Error (Test
Mode DTC)1. Vehicle speed sensor
2. Tire pressure warning ECU
3. Combination meter
4. Wire harness or connectorTW-70 DTC Code Detection Item Trouble Area See page