2007 TOYOTA SIENNA ECU

BC–128BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
(a) Remove the ECU-IG fuse from the driver side J/B.
DTC C1241/41 Low Battery Positive Voltage
DTC Code DTC Detection Condition Trouble Area
C1241/41When any of the following is detected:
1. At a vehicle speed of 3 km/h (2mph) or more, the
IG1 terminal voltage is 9.5 V or less for 10 sec. or
more.
2. When the solenoid relay remains ON and the IG1
terminal voltage is 9.5 V or less, the relay contact is
open for 0.2 sec. or more.
3. While the motor fail safe relay is ON after motor
relay ON, the IG1 terminal voltage is 9.5 V or less
and the actuator pump drive motor is OFF for 0.1
sec. or more.•Battery
• Charging system
• Power source circuit
1INSPECT ECU-IG FUSE
F045116E06

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–129
BC
(b) Check continuity of the ECU-IG fuse.
Standard resistance
NG
OK
(a) Check the positive battery voltage.
Standard voltage:
11 to 14 V
NG
OK
(a) WHEN USING INTELLIGENT TESTER:
(1) Connect the intelligent tester to the DLC3.
(2) Start the engine.
(3) Select the DATA LIST mode on the intelligent tester.
ABS / VSC:
(4) Check that the voltage condition output from the
ECU displayed on the intelligent tester.
OK:
"Normal" is displayed.
(b) WHEN NOT USING INTELLIGENT TESTER:
(1) Disconnect the skid control ECU connector.
(2) Turn the ignition switch to the ON position.
(3) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70).
NG
F045093E09
Tester Connection Specified condition
ECU-IG Fuse Below 1
REPLACE ECU-IG FUSE
2CHECK BATTERY
CHECK OR REPLACE CHARGING SYSTEM
OR BATTERY
3INSPECT SKID CONTROL ECU (IG1 TERMINAL)
Tester Display Measurement Item/Range Normal Condition
IG VOLTAGEECU power supply voltage / UNDER /
NORMALNORMAL: 9.5 V or over
UNDER: Below 9.5 V
G024767E42
Tester Connection Specified Condition
S3-46 (IG1) - S3-32 (GND1) 10 to 14 V
S3-46 (IG1) - S3-1 (GND2) 10 to 14 V
Go to step 4

BC–130BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
OK
(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK REPLACE BRAKE ACTUATOR ASSEMBLY
4INSPECT SKID CONTROL ECU (GND TERMINAL)
G024767E43
Tester Connection Specified Condition
S3-32 (GND1) - Body ground Below 1
S3-1 (GND2) - Body ground Below 1
REPAIR OR REPLACE HARNESS OR
CONNECTOR (GND CIRCUIT)
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–131
BC
DESCRIPTION
Master cylinder pressure sensor is connected to the skid control ECU in the actuator.
INSPECTION PROCEDURE
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine.
(c) Select the DATA LIST mode on the intelligent tester.
ABS / VSC:
(d) Check that the brake fluid pressure value of the master
cylinder pressure sensor indicated on the intelligent
tester, changes when the brake pedal is depressed.
OK:
Brake fluid pressure value should change.
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70).
NG
OK
DTC C1246/46 Master Cylinder Pressure Sensor Malfunction
DTC Code DTC Detection Condition Trouble Area
C1246/46When any of the following is detected:
1. When the vehicle speed is 7 km/h (4 mph) or more
and PMC terminal voltage of skid control ECU
exceeds 0.86 V, the condition that the voltage does
not change by 0.005 V or more continues for 30
sec.
2. Noise in terminal PMC of skid control ECU occurs 7
times or more within 5 sec.
3. When the stop light switch is off, the condition that
PMC terminal voltage of skid control ECU is 0.86 V
or more, or less than 0.3 V continues for 5 sec. or
more.
4. When IG1 terminal voltage is between 9.5 and 17.2
V, the condition that the VCM terminal voltage of
skid control ECU is out of the range from 4.4 to 5.6
V continues for 1.2 sec. or more.
5. When VCM terminal voltage of skid control ECU is
between 4.4 and 5.6 V, the condition that the PMC
terminal voltage of skid control ECU is out of the
range from 0.14 to 4.85 V continues for 1.2 sec. or
more.• Master cylinder pressure sensor
• Master cylinder pressure sensor circuit
1READ VALUE ON INTELLIGENT TESTER (MASTER CYLINDER PRESSURE SENSOR)
Tester Display Measurement Item/Range Normal Condition
MAS CYL PRS 1Master cylinder pressure sensor 1 reading /
min.: 0 V, max.: 5 VWhen brake pedal is released : 0.3 to 0.9 V
Go to step 2
REPLACE BRAKE ACTUATOR ASSEMBLY

BC–132BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70).
NG
OK
2INSPECT SKID CONTROL ECU (STP1 TERMINAL)
G024767E58
Tester Connection Condition Specified Condition
S3-27 (STP1) - Body
groundBrake pedal depressed 8 to 14 V
S3-27 (STP1) - Body
groundBrake pedal depressed Below 1 V
REPAIR OR REPLACE STOP LIGHT SWITCH
CIRCUIT
REPLACE BRAKE ACTUATOR ASSEMBLY

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–135
BC
INSPECTION PROCEDURE
(a) Check that the stop light comes on when the brake pedal
is depressed and goes off when the brake pedal is
released.
OK
HINT:
Check the stop light bulb as it may have burnt out.
NG
OK
(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the
table below.
Standard voltage
NG
OK
(a) Clear the DTCs (See page BC-82).
(b) Turn the ignition switch to the ON position.
(c) Are the same DTCs detected?
Result
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70).
B
1CHECK STOP LIGHT SWITCH OPERATION
Pedal Condition Illumination Condition
Brake pedal depressedON
Brake pedal releasedOFF
Go to step 4
2INSPECT SKID CONTROL ECU (STP1 TERMINAL)
G024767E58
Tester Connection Condition Specified Condition
S3-27 (STP1) - Body
groundBrake pedal depressed 8 to 14 V
S3-27 (STP1) - Body
groundBrake pedal released Below 1 V
Go to step 5
3RECONFIRM DTC
Result Proceed to
DTC is outputA
DTC is not outputB
PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE

BC–136BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
A
(a) Disconnect the stop light switch assembly connector.
(b) Measure the resistance according to the value(s) in the
table below.
Standard resistance
NG
OK
(a) Disconnect the stop light switch connector and skid
control ECU connector.
(b) 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 REPLACE BRAKE ACTUATOR ASSEMBLY
4INSPECT STOP LIGHT SWITCH
C146625E04
Tester connection Switch condition Specified condition
1 - 2 Switch pin free Below 1
1 - 2 Switch pin pushed in 10 k or higher
REPLACE STOP LIGHT SWITCH
5CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - SKID CONTROL ECU)
G026188E08
Tester Connection Specified Condition
S3-27 (STP1) - S12-1 (STP) Below 1
REPAIR OR REPLACE HARNESS OR
CONNECTOR

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–139
BC
(c) Select the ACTIVE TEST mode on the intelligent tester.
ABS / VSC:
(d) Check the operation sound of the ABS motor individually
when operating it with the intelligent tester.
OK:
The operation sound of the ABS motor should be
heard.
NOTICE:
When replacing the brake actuator assembly,
perform zero point calibration (See page BC-70).
NG
OK
(a) Disconnect the skid control ECU connector.
(b) 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
Tester Display Test Part Control Range Diagnostic Note
ABS MOT RELAY ABS motor relay Relay ON / OFFOperation of motor (clicking
sound) can be heard
Go to step 2
REPLACE BRAKE ACTUATOR ASSEMBLY
2INSPECT SKID CONTROL ECU (GND2 TERMINAL)
G024767E59
Tester Connection Specified Condition
S3-1 (GND2) - Body ground Below 1
REPAIR OR REPLACE HARNESS OR
CONNECTOR (GND2 CIRCUIT)
REPLACE BRAKE ACTUATOR ASSEMBLY