2007 TOYOTA SIENNA ECU

TW–42TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
DESCRIPTION
The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies
measure the air pressures of the tires. The measured values 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. The
ECU compares the measured air pressure values with the air pressure threshold. When the measured air
pressure value is less than this threshold, the warning light in the combination meter comes on. The tire
pressure warning ECU stores a DTC when the tire pressure warning valve and transmitter stops
transmitting signals. At this time, forcibly transmit the signals by releasing the tire pressure rapidly. The
stored DTC is cleared when the signal transmission is resumed.
HINT:
It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is
malfunctioning because it cannot be identified by the output DTC.
INSPECTION PROCEDURE
NOTICE:
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 and/or valve and transmitter have
been replaced.
(a) Set the tire pressure to the specified value.
Cold tire inflation pressure
(b) Make sure that the ignition switch is off.
(c) Connect the intelligent tester to the DLC3.
(d) Turn the ignition switch to the ON position and turn the
tester on.
DTC C2111/11 Transmitter ID1 Operation Stop
DTC C2112/12 Transmitter ID2 Operation Stop
DTC C2113/13 Transmitter ID3 Operation Stop
DTC C2114/14 Transmitter ID4 Operation Stop
DTC No. DTC Detection Condition Trouble Area
C 2 111 / 11
C2112/12
C2113/13
C2114/14Tire pressure warning valve and transmitters stop
transmitting signals• Tire pressure warning valve and transmitter
• Tire pressure warning ECU
1PERFORM FORCED TRANSMISSION OF TRANSMITTER ID OF ALL WHEELS
Tire Size
kPa (kgf/cm2, psi)
P215/65R16
240 (2.4, 35)
P225/60R17

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–45
TW
DESCRIPTION
The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies
measure the air pressure of the tires. The measured values 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. The
ECU compares the measured air pressure values with the air pressure threshold. When the measured air
pressure value is less than this threshold, the warning light in the combination meter comes on.
The tire pressure warning valve and transmitters constantly send radio waves to the tire pressure warning
antenna and receiver.
Under the following conditions below, the tire pressure warning antenna and receiver is unable to receive
the signals from the tire pressure warning valves and transmitters, and a DTC is stored.
• Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.
• Devices using similar radio frequencies are used in the vehicle.
• The goods which obstruct the radio signal of the valve and transmitter, for example, tire chain or
window film.
HINT:
When no signals are received for 20 minutes or more, a DTC is output.
DTCs from C2121/21 to C2124/24 can only be cleared by using the tester. DTCs from C2181/81 to
C2184/84 can be cleared when the transmitter in the tire pressure warning valve and transmitter sends a
forced transmission signal or test mode ends. DTCs from C2181/81 to C2184/84 are output only in test
mode.
HINT:
It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is
malfunctioning because it cannot be identified by the output DTC.
DTC C2121/21 No Signal from Transmitter ID1
DTC C2122/22 No Signal from Transmitter ID2
DTC C2123/23 No Signal from Transmitter ID3
DTC C2124/24 No Signal from Transmitter ID4
DTC C2181/81 Transmitter ID1 not Received (Test Mode DTC)
DTC C2182/82 Transmitter ID2 not Received (Test Mode DTC)
DTC C2183/83 Transmitter ID3 not Received (Test Mode DTC)
DTC C2184/84 Transmitter ID4 not Received (Test Mode DTC)
DTC No. DTC Detection Condition Trouble Area
C2121/21
C2122/22
C2123/23
C2124/24These DTCs are detected when no signals are received
for 20 minute drive or more.• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECU
C2181/81
C2182/82
C2183/83
C2184/84Malfunction in the transmitting/receiving circuit• Tire pressure warning valve and transmitter
• Tire pressure warning antenna and receiver
• Wire harness or connector
• Tire pressure warning ECU

TW–46TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
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 and/or valve and
transmitter have been replaced.
(a) Check if the vehicle is not located in areas such as
described below:
1CHECK FREQUENCY RECEIVING CONDITION
B166325E02

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–49
TW
(a) Disconnect the T15 ECU connector.
(b) Disconnect the T16 receiver connector.
(c) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(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 REGIT ID CODE by following the prompts
displayed on the intelligent tester.
TIRE PRESSURE:
(e) Check the ID number on the identified transmitter by
removing it from the tire and wheel.
3CHECK HARNESS AND CONNECTOR (ECU - RECEIVER)
C148708E14
Tester Connection Condition Specified Condition
T15-12 (RDA) - T16-1
(RDA)
AlwaysBelow 1
T15-11 (GND2) - T16-4
(GND)
T15-6 (RF5V) - T16-5
(+5V)
T15-12 (RDA) - Body
ground
10 k
or higher T15-11 (GND2) - Body
ground
T15-6 (RF5V) - Body
ground
REPAIR OR REPLACE HARNESS OR
CONNECTOR
4INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER
Tester Display Measurement Item/Range Normal Condition Diagnostic Note
REGIT ID1 CODERegistered ID1 code/
min.: 0, max.: FFFFFF*The ID No. registered in the
transmitter ID1 is displayed*: Displayed only when the ID No.
is not registered.
REGIT ID2 CODERegistered ID2 code/
min.: 0, max.: FFFFFF*The ID No. registered in the
transmitter ID2 is displayed*: Displayed only when the ID No.
is not registered.
REGIT ID3 CODERegistered ID3 code/
min.: 0, max.: FFFFFF*The ID No. registered in the
transmitter ID3 is displayed*: Displayed only when the ID No.
is not registered.
REGIT ID4 CODERegistered ID4 code/
min.: 0, max.: FFFFFF*The ID No. registered in the
transmitter ID4 is displayed*: Displayed only when the ID No.
is not registered.

TW–52TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
HINT:
*: It may take about 5 to 6 minutes until the values are
displayed.
Result
B
A
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.*
TIREPRESS3ID3 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.*
TIREPRESS4ID4 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.* Tester Display Measurement Item/Range Normal Condition Diagnostic Note
Result Proceed to
All tire pressure readings are equal to specified values. A
Tire pressure values are not displayed. B
REPLACE TIRE PRESSURE WARNING ECU
(See page TW-87)
END

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–53
TW
DESCRIPTION
The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies
measure the air pressure of the tires. The measured values 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. The
ECU compares the measured air pressure values with the air pressure threshold. When the measured air
pressure value is less than this threshold, the warning light in the combination meter comes on.
When the internal circuit of the tire pressure warning valve and transmitter is malfunctioning, this DTC is
output.
HINT:
It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is
malfunctioning because it cannot be identified by the output DTC.
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 and/or valve and
transmitter have been replaced.
(a) Set the tire pressure to the specified value.
Cold tire inflation pressure
(b) Make sure that the ignition switch is off.
(c) Connect the intelligent tester to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Display the "TIREPRESS" data for each wheel using the
intelligent tester.
DTC C2141/41 Transmitter ID1 Error
DTC C2142/42 Transmitter ID2 Error
DTC C2143/43 Transmitter ID3 Error
DTC C2144/44 Transmitter ID4 Error
DTC No. DTC Detection Condition Trouble Area
C2141/41
C2142/42
C2143/43
C2144/44The battery of the valve and transmitter is expired.• Tire pressure warning valve and transmitter
• Tire pressure warning ECU
1IDENTIFY TRANSMITTER CORRESPONDING TO DTC
Tire Size
kPa (kgf/cm2, psi)
P215/65R16
240 (2.4, 35)
P225/60R17

TW–56TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEM
TW
HINT:
*: It may take about 5 to 6 minutes until the values are
displayed. If the values are not displayed after a few
minutes, perform troubleshooting according to the
inspection procedure for DTCs C2121/21 to C2124/24
(See page TW-35).
Result
B
A
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.*
TIREPRESS4ID4 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.* Tester Display Measurement Item/Range Normal Condition Diagnostic Note
Condition Proceed to
Tire pressure values are not displayed. A
All tire pressure readings are equal to specified values. B
END
REPLACE TIRE PRESSURE WARNING ECU (See page TW-87)

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–57
TW
DESCRIPTION
Each tire pressure warning valve and transmitter measures the internal temperature of its tire as well as
tire pressure, and transmits the information to the tire pressure warning ECU along with the transmitter ID.
If the measured temperature is out of the specified range, the tire pressure warning ECU recognizes it as
a malfunction, outputs DTCs, and illuminates the tire pressure warning light after blinking for 1 minute.
HINT:
It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is
malfunctioning because it cannot be identified by the output DTC.
INSPECTION PROCEDURE
NOTICE:
• When replacing the tire pressure warning ECU, read the IDs stored in the ECU using the
intelligent tester and note 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 and/or valve and
transmitter have been replaced.
(a) Check the tire is not flat, and there is no indication of air
pressure drop.
OK:
Tire is normal.
HINT:
If a tire is damaged, the tire pressure warning valve and
transmitter may also have been damaged at the same
time.
NG
OK
(a) Set the tire pressure to the specified value.
DTC C2165/65 Abnormal Temperature Inside ID1 Tire
DTC C2166/66 Abnormal Temperature Inside ID2 Tire
DTC C2167/67 Abnormal Temperature Inside ID3 Tire
DTC C2168/68 Abnormal Temperature Inside ID4 Tire
DTC No. DTC Detection Condition Trouble Area
C2165/65
C2166/66
C2167/67
C2168/68Temperature inside the tire exceeds 119
C (246.2F).•Tires
• Tire pressure warning valve and transmitter
• Tire pressure warning ECU
1CHECK TIRES
REPLACE TIRE AND TIRE PRESSURE
WARNING VALVE AND TRANSMITTER (See
page TW-84)
2IDENTIFY TRANSMITTER CORRESPONDING TO DTC