TOYOTA SIENNA 2007 Service Repair Manual

BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEMBC–33
BC
DESCRIPTION
The ABS motor relay supplies power to the ABS pump motor. While the ABS is activated, the ECU turns
the motor relay on and operates the ABS pump motor.
If the voltage supplied to the motor relay (+BM) is below the DTCs detection threshold due to low voltage
from the battery/alternator, the DTCs may be stored.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
After steps 1, 2 and 3 are completed, start the inspection from step 4 when using the intelligent tester, and
from step 5 when not using the intelligent tester.
(a) Remove the ABS 1 fuse from the FL block.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
DTC C0273/13 Open in ABS Motor Relay Circuit
DTC C0274/14 Short to B+ in ABS Motor Relay Circuit
DTC No. DTC Detection Condition Trouble Area
C0273/13With the IG1 terminal voltage 10 V or less during initial
check or ABS control, pump motor relay is turned ON
and relay contact is not ON for 0.2 seconds or more.• ABS 1 fuse
• ABS motor relay
• ABS motor relay circuit
• Brake actuator assembly
C0274/14The motor contact is ON for 3 seconds or more when
the motor relay is OFF.• ABS 1 fuse
• ABS motor relay
• ABS motor relay circuit
• Brake actuator assembly
1INSPECT FUSE (ABS 1 FUSE)
C119436E01
Tester Connection Specified Condition
ABS 1 (50 A) fuse Below 1
(Continuity)

BC–34BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEM
BC
NG
OK
(a) Install the ABS 1 fuse.
(b) Disconnect the skid control ECU connector.
(c) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NG
OK
(a) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(a) Reconnect the skid control ECU connector.
(b) Connect the intelligent tester to the DLC3.
(c) Turn the ignition switch to the ON position and turn the
intelligent tester main switch on.
(d) Start the engine.
(e) Select the ACTIVE TEST mode on the intelligent tester.
ABS:REPLACE FUSE (ABS 1 FUSE)
2INSPECT SKID CONTROL ECU (+BM TERMINAL VOLTAGE)
C113872E02
Tester Connection Condition Specified Condition
S3-24 (+BM) - Body
groundAlways 10 to 14 V
REPAIR OR REPLACE HARNESS OR
CONNECTOR (+BM CIRCUIT)
3INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)
C058919E22
Tester Connection Specified Condition
S3-1 (GND1) - Body ground Below 1
S3-23 (GND2) - Body ground Below 1
REPAIR OR REPLACE HARNESS OR
CONNECTOR (GND CIRCUIT)
4PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ABS MOTOR RELAY)
Item (Display) Vehicle Condition / Test Details Diagnostic Note
ABS MOT RELAY Turns ABS motor relay ON / OFF Operating sound of motor is heard

BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEMBC–35
BC
(f) Check operating sound of the ABS motor when
operating it with the intelligent tester.
OK:
The operating sound of the ABS motor is heard.
NG
OK
(a) Clear the DTCs (See page BC-10).
(b) Start the engine.
(c) Drive the vehicle at the speed of 6 km/h (4 mph) or more.
(d) Check that the same DTCs are recorded (See page BC-
10).
HINT:
• Reinstall the sensors, connectors, etc. and restore the
vehicle to its prior condition before rechecking for
DTCs.
• If a speed signal of 6 km/h (4 mph) or more is input to
the skid control ECU, with the ignition switch on and
the stop light switch off, the ECU performs self-
diagnosis of the motor and solenoid circuits.
Result
HINT:
• If any DTCs are output while jiggling a connector or
wire harness of the brake actuator (skid control ECU),
inspect and repair the connector or wire harness.
• If the normal system code is output, slightly jiggle the
connectors, wire harnesses, and fuses of the brake
actuator assembly. Make sure that no DTCs are
output.
• These DTCs may be stored due to a malfunction in
the connector terminal connection, etc.
B
AREPLACE BRAKE ACTUATOR ASSEMBLY
5RECONFIRM DTC
Condition Proceed to
DTCs (C0273/13 and C0274/14) are output A
DTCs (C0273/13 and C0274/14) are not output B
END
REPLACE BRAKE ACTUATOR ASSEMBLY

BRAKE CONTROL – REAR SPEED SENSOR (for 4WD)BC–193
BC
BRAKE
BRAKE CONTROL
REAR SPEED SENSOR (for 4WD)
COMPONENTS
C119321E12

BC–194BRAKE CONTROL – REAR SPEED SENSOR (for 4WD)
BC
REMOVAL
HINT:
Remove the RH side by the same procedure as the LH side.
1. REMOVE REAR WHEEL
2. REMOVE QUARTER TRIM PANEL ASSEMBLY
FRONT LH
HINT:
Remove the LH side by the same procedure as the RH
side (See page IR-9).
3. REMOVE REAR SPEED SENSOR
(a) Disconnect the speed sensor connector, and pull
out the sensor wire harness with grommet.
(b) Remove the clamp bolt holding the sensor harness
from the body.
(c) Remove the bolt and speed sensor rear LH.
NOTICE:
Keep the tip of the speed sensor rear LH clean.
F040305
G024305
G023898

BC–36BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEM
BC
DESCRIPTION
This relay supplies power to each ABS solenoid.
Immediately after the ignition switch is turned to the ON position, the relay turns on if the solenoid is
determined to be normal as a result of self-diagnosis during initial check.
The relay turns off if an open/short is detected.
If the voltage supplied to the motor relay (+BS) is below the DTC detection threshold due to low voltage
from the battery/alternator, the DTCs may be stored.
WIRING DIAGRAM
Refer to DTCs C0226/21, C0236/22, C0246/23 and C0256/24 (See page BC-29).
INSPECTION PROCEDURE
(a) Remove the ABS 2 fuse from the FL block.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
DTC C0278/11 Open in ABS Solenoid Relay Circuit
DTC C0279/12 Short to B+ in ABS Solenoid Relay Circuit
DTC No. DTC Detection Condition Trouble Area
C0278/11The solenoid relay contact is OFF for 0.2 seconds or
more when the solenoid relay is turned ON.• ABS 2 fuse
• ABS solenoid relay
• ABS solenoid relay circuit
• Brake actuator assembly
C0279/12The solenoid relay contact is ON for 0.2 seconds or
more when the solenoid relay is OFF.• ABS 2 fuse
• ABS solenoid relay
• ABS solenoid relay circuit
• Brake actuator assembly
1INSPECT FUSE (ABS 2 FUSE)
Tester Connection Specified Condition
ABS 2 (30 A) fuse Below 1
(Continuity)
REPLACE FUSE (ABS 2 FUSE)

BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEMBC–37
BC
(a) Install the ABS 2 fuse.
(b) Disconnect the skid control ECU connector.
(c) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NG
OK
(a) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(a) Clear the DTCs (See page BC-10).
(b) Start the engine.
(c) Drive the vehicle at the speed of 6 km/h (4 mph) or more.
(d) Check that the same DTCs are recorded (See page BC-
10).
HINT:
• Reinstall the sensors, connectors, etc. and restore the
vehicle to its prior condition before rechecking for
DTCs.
• If a speed signal of 6 km/h (4 mph) or more is input to
the skid control ECU, with the ignition switch on and
the stop light switch off, the ECU performs self-
diagnosis of the motor and solenoid circuits.
Result
2INSPECT SKID CONTROL ECU (+BS TERMINAL VOLTAGE)
C058919E23
Tester Connection Condition Specified Condition
S3-2 (+BS) - Body
groundAlways 10 to 14 V
REPAIR OR REPLACE HARNESS OR
CONNECTOR (+BS CIRCUIT)
3INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)
C058919E22
Tester Connection Specified Condition
S3-1 (GND1) - Body ground Below 1
S3-23 (GND2) - Body ground Below 1
REPAIR OR REPLACE HARNESS OR
CONNECTOR (GND CIRCUIT)
4RECONFIRM DTC
Condition Proceed to
DTCs (C0278/11 and C0279/12) are output A
DTCs (C0278/11 and C0279/12) are not output B

BC–38BRAKE CONTROL – ANTI-LOCK BRAKE SYSTEM
BC
HINT:
• If any DTCs are output while jiggling a connector or
wire harness of the brake actuator (skid control ECU),
inspect and repair the connector or wire harness.
• If the normal system code is output, slightly jiggle the
connectors, wire harnesses, and fuses of the brake
actuator assembly. Make sure that no DTCs are
output.
• These DTCs may be memorized due to a malfunction
in the connector terminal connection, etc.
B
AEND
REPLACE BRAKE ACTUATOR ASSEMBLY

BC–196BRAKE CONTROL – YAW RATE AND DECELERATION SENSOR
BC
BRAKE
BRAKE CONTROL
YAW RATE AND DECELERATION SENSOR
COMPONENTS
C119321E13

BRAKE CONTROL – YAW RATE AND DECELERATION SENSORBC–197
BC
REMOVAL
HINT:
• Don't use the dropped or damaged yawrate sensor.
• Free from the foreign matters between yaerate sensor
bracket and body.
• Make sure the sensor direction.
1. REMOVE FRONT SEAT ASSEMBLY RH
HINT:
See page SE-40.
2. REMOVE FRONT DOOR SCUFF PLATE RH
3. REMOVE COWL SIDE TRIM BOARD RH
(a) Remove the nut and cowl side trim board plate RH.
4. REMOVE YAW RATE AND DECELERATION SENSOR
(a) Disconnect the yawrate sensor connector.
(b) Remove the 2 bolts and yawrate sensor.
G024259