2007 TOYOTA SIENNA ECU

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–167
BC
Result
B
A
(a) Check if the multiplex communication system DTC is
output (See page MP-14).
Result
B
A
(a) Check if the skid control ECU connector is securely
connected.
OK:
The connector is securely connected.
NG
OK
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
NG
OK
(a) Perform Active Test of the combination meter (meter
CPU) using the intelligent tester (See page ME-19).
Result Proceed to
CAN communication system DTC is not output A
CAN communication system DTC is output B
INSPECT CAN COMMUNICATION SYSTEM
2CHECK MULTIPLEX COMMUNICATION SYSTEM
Result Proceed to
Multiplex communication system DTC is not output A
Multiplex communication system DTC is output B
INSPECT MULTIPLEX COMMUNICATION
SYSTEM
3CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED
CONNECT CONNECTOR TO ECU
CORRECTLY
4CHECK BATTERY
CHECK OR REPLACE CHARGING SYSTEM
OR BATTERY
5INSPECT COMBINATION METER ASSEMBLY

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–169
BC
DESCRIPTION
The skid control ECU is connected to the combination meter via CAN and multiplex communications.
The SLIP indicator blinks during VSC and/or TRAC operation.
When the system fails, the SLIP indicator comes on to warn the driver.
WIRING DIAGRAM
Refer to Slip Indicator Light Remains ON (See page BC-164).
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (See page BC-70).
(a) Check if the CAN communication system DTC is output
(See page CA-17).
Result
B
A
(a) Check if the multiplex communication system DTC is
output (See page MP-14).
Result
B
A
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine.
(c) Select the Active Test mode on the intelligent tester (See
page BC-85).
ABS / VSC:
Slip Indicator Light does not Come ON
1CHECK CAN COMMUNICATION SYSTEM
Result Proceed to
CAN communication system DTC is not output A
CAN communication system DTC is output B
INSPECT CAN COMMUNICATION SYSTEM
2CHECK MULTIPLEX COMMUNICATION SYSTEM
Result Proceed to
Multiplex communication system DTC is not output A
Multiplex communication system DTC is output B
INSPECT MULTIPLEX COMMUNICATION
SYSTEM
3CHECK SLIP INDICATOR LIGHT
Tester Display Test Part Control Range Diagnostic Note
SLIP INDI LIGHT SLIP indicator light Indicator light ON / OFF Observe combination meter

BC–172BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
OK
(a) Disconnect the skid control buzzer connector.
(b) Apply battery negative voltage to terminal 1, and battery
positive voltage to terminal 2 of the skid control buzzer
connector, and check that the buzzer sounds.
OK:
The skid control buzzer sound should be heard.
NG
OK
(a) Disconnect the skid control buzzer connector and the
skid control ECU connector.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
(c) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70)
NG
OK REPLACE BRAKE ACTUATOR ASSEMBLY
2INSPECT SKID CONTROL BUZZER
F002192E10
REPLACE SKID CONTROL BUZZER
3CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - SKID CONTROL ECU)
G026280E05
Tester Connection Specified Condition
S3-30 (BZ) - V6-1 (BZ) Below 1
Tester Connection Specified Condition
S3-30 (BZ) - Body ground 10 k
or higher
REPAIR OR REPLACE HARNESS OR
CONNECTOR
REPLACE BRAKE ACTUATOR ASSEMBLY

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–173
BC
DESCRIPTION
Connecting terminals TC and CG of the DLC3 causes the ECU to display the DTC by blinking the ABS
warning light and/or VSC warning light.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (See page BC-70).
(a) Check if the CAN communication system DTC is output
(See page BC-82).
Result
B
TC and CG Terminal Circuit
1CHECK CAN COMMUNICATION SYSTEM
C136991E03
Result Proceed to
CAN communication system DTC is not output A
CAN communication system DTC is output B
INSPECT CAN COMMUNICATION SYSTEM

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–177
BC
DESCRIPTION
In the sensor check mode, a malfunction of the speed sensor that cannot be detected when the vehicle is
stopped is detected while driving.
Transition to the sensor check mode can be performed by connecting terminals TS and CG of the DLC3
and turning the ignition switch from off to the ON position.
WIRING DIAGRAM
INSPECTION PROCEDURE
(a) Turn the ignition switch to the ON position.
(b) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NG
OK
(a) Disconnect the skid control ECU connector.
TS and CG Terminal Circuit
1INSPECT DLC3
F045121E03
E106867E20
Tester Connection Specified Condition
D1-12 (TS) - D1-4 (CG) 10 to 14 V
REPAIR OR REPLACE HARNESS OR
CONNECTOR
2CHECK HARNESS AND CONNECTOR (TS of DLC3 - SKID CONTROL ECU)

BC–18BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEM
BC
Test Mode DTC of ABS:
C1236/36Foreign Object is Attached on Tip
of Front Speed Sensor LH1. Front speed sensor LH
2. Speed sensor rotor
3. Sensor installation
4. Brake actuator assemblyBC-17
C1238/38Foreign Object is Attached on Tip
of Rear Speed Sensor RH1. Rear speed sensor RH
2. Speed sensor rotor
3. Sensor installation
4. Brake actuator assemblyBC-23
C1239/39Foreign Object is Attached on Tip
of Rear Speed Sensor LH1. Rear speed sensor LH
2. Speed sensor rotor
3. Sensor installation
4. Brake actuator assemblyBC-23
C1241/41 Low Battery Positive Voltage1. Battery
2. ECU-IG fuse
3. Charging system
4. Power source circuitBC-37
C1249/49 Open in Stop Light Switch Circuit1. Stop light switch
2. Stop light switch circuitBC-41
C1251/51 Open in Pump Motor Circuit1. ABS pump motor circuit
2. Brake actuator assemblyBC-45
DTC Code Detection Item Trouble Area See page
C1271/71Low Output Signal of Front Speed
Sensor RH (Test Mode DTC)1. Front speed sensor RH
2. Sensor installation
3. Speed sensor rotorBC-17
C1272/72Low Output Signal of Front Speed
Sensor LH (Test Mode DTC)1. Front speed sensor LH
2. Sensor installation
3. Speed sensor rotorBC-17
C1273/73Low Output Signal of Rear Speed
Sensor RH (Test Mode DTC)1. Rear speed sensor RH
2. Sensor installation
3. Speed sensor rotorBC-23
C1274/74Low Output Signal of Rear Speed
Sensor LH (Test Mode DTC)1. Rear speed sensor LH
2. Sensor installation
3. Speed sensor rotorBC-23
C1275/75Abnormal Change in Output
Signal of Front Speed Sensor RH
(Test Mode DTC)Speed sensor rotorBC-17
C1276/76Abnormal Change in Output
Signal of Front Speed Sensor LH
(Test Mode DTC)Speed sensor rotorBC-17
C1277/77Abnormal Change in Output
Signal of Rear Speed Sensor RH
(Test Mode DTC)Speed sensor rotorBC-23
C1278/78Abnormal Change in Output
Signal of Rear Speed Sensor LH
(Test Mode DTC)Speed sensor rotorBC-23 DTC Code Detection Item Trouble Area See page

BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEMBC–19
BC
DESCRIPTION
The speed sensor detects wheel speed and transmits the appropriate signals to the ECU. These signals
are used for control of the ABS control system. The front and rear rotors have 48 serrations each.
When the rotors rotate, the magnetic field generated by the permanent magnet in the speed sensor
induces an AC voltage.
Since the frequency of this AC voltage changes in direct proportion to the speed of the rotor, the
frequency is used by the ECU to detect the speed of each wheel.
DTCs C1271/71 to C1276/76 can be deleted when the speed sensor sends a vehicle speed signal or the
Test Mode ends. DTCs C1271/71 to C1276/76 are output only in the Test Mode.
DTC C0200/31 Front Speed Sensor RH Circuit
DTC C0205/32 Front Speed Sensor LH Circuit
DTC C1235/35Foreign Object is Attached on Tip of Front
Speed Sensor RH
DTC C1236/36Foreign Object is Attached on Tip of Front
Speed Sensor LH
DTC C1271/71Low Output Signal of Front Speed Sensor RH
(Test Mode DTC)
DTC C1272/72Low Output Signal of Front Speed Sensor LH
(Test Mode DTC)
DTC C1275/75Abnormal Change in Output Signal of Front
Speed Sensor RH (Test Mode DTC)
DTC C1276/76Abnormal Change in Output Signal of Front
Speed Sensor LH (Test Mode DTC)
F000010E04

BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEMBC–23
BC
(a) Disconnect the skid control sensor wire.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
RH:
LH:
NG
OK
(a) Connect the oscilloscope to terminals FR+ - FR- or FL+ -
FL- of the skid control ECU.
(b) Drive the vehicle at about 30 km/h(19 mph), and check
the signal waveform.
OK:
A waveform as shown in the figure should be
output.
HINT:
• As vehicle speed (wheel rotation speed) increases,
the width of the waveform narrows and the fluctuation
in the output voltage becomes greater.
• When noise is identified in the waveform on the
oscilloscope, error signals are generated due to rotor
scratches, looseness or foreign matter attached to the
speed sensor.
NG
6CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND FRONT
SPEED SENSOR)
C161174E02
Tester Connection Specified Condition
S3-27 (FR+) - A4-1 (FR+) Below 1
S3-27 (FR+) - Body ground 10 k or higher
S3-28 (FR-) - A4-2 (FR-) Below 1
S3-28 (FR-) - Body ground 10 k or higher
Tester Connection Specified Condition
S3-13 (FL+) - A3-1 (FL+) Below 1
S3-13 (FL+) - Body ground 10 k or higher
S3-26 (FL-) - A3-2 (FL-) Below 1
S3-26 (FL-) - Body ground 10 k or higher
REPAIR OR REPLACE HARNESS OR
CONNECTOR
7INSPECT SPEED SENSOR AND SENSOR ROTOR SERRATIONS
W004200E03
Go to step 9