2001 TOYOTA SEQUOIA VSC system

F02135
Start Position
End PositionWithin ± 5° DI±900
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1094 Author: Date:
2005 SEQUOIA (RM1146U)
(b) Check the yaw rate and deceleration sensor.
Shift the shift lever to the D position and drive the vehicle
at a vehicle speed of approx. 3 mph (5 km/h), turn the
steering wheel either to the left or right for 90° or more,
and turn the vehicle through 180 degrees. Check that the
VSC buzzer sounds for 3 seconds upon start off.
Stop the vehicle and shift the shift lever to the P position,
and check that the VSC buzzer sounds again for 3 se-
conds.
HINT:

If the VSC buzzer sounds twice, the sensor check has
been completed normally.

If the VSC buzzer does not sound, check the VSC buzzer
circuit (See page DI±1052), then do the sensor check
again.

Drive the vehicle through 180°. At the end of the turn, the
direction of the vehicle should be within 180° ± 5° of its
start position.

Do not spin the wheels.

If the buzzer sounds after start off, then the deceleration
sensor check has passed its check. If the buzzer sounds
at the completion of a curve, then the yaw rate sensor
check has passed its check. The buzzer sound should be
heard twice during the sensor checks.
(c) Check the master cylinder pressure sensor.
(1) Turn the ignition switch to the ON position.
(2) Keep the vehicle in a stationary condition on a level
surface for 2 sec. or more.
(3) Keeping the vehicle in a stationary condition and
not pressing on the brake pedal for 1 sec. or more,
depress the brake pedal with 147 N (15 kgf, 33 lbf)
or more for 2 sec. or more.
NOTICE:
If zero point calibration has never been performed on a new
ECU, master cylinder pressure sensor check cannot be
completed correctly. Perform zero point calibration first
(See page DI±897).
HINT:
At this time, the buzzer sounds for 3 seconds.
(d) Check the speed sensor.
Drive the vehicle straight forward.
When driving the vehicle at the speed of 28 mph (45 km/h)
or higher for several seconds, check that the ABS warn-
ing light goes off.
HINT:
There is a possibility that the sensor check is not completed if
the vehicle has its wheels spun or its steering wheel turned dur-
ing this check.
(e) Stop the vehicle.

F09750
CG TcDLC3
BR3893
Trouble Code (Example Code 72, 76)
ON
OFF
4 sec. 1.5 sec.
Repeat 2.5 sec.
0.5 sec. 0.5 sec. 0.5 sec. 0.5 sec.7726
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±901
1095 Author: Date:
2005 SEQUOIA (RM1146U)
(f) Read the DTC.
(1) Using SST, connect terminals Tc and CG of the
DLC3.
SST 09843±18040
(2) Read the number of blinks of the warning light.
HINT:

See the list of DTC (step 3).

If all sensors are normal, a normal system code is output
(A cycle of 0.25 sec. ON and 0.25 sec. OFF is repeated).

If 2 or more malfunctions are indicated at the same time,
the codes will be displayed in ascending order.
(3) After doing the check, disconnect terminals Ts and
CG, Tc and CG of the DLC3, and turn the ignition
switch OFF.
SST 09843±18040

D05981
Hand±held
Tester
DLC3
BR3904
0.13 sec. 0.13 sec.
ON
OFF
F02135
Start Position
End PositionWithin ± 5° DI±902
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1096 Author: Date:
2005 SEQUOIA (RM1146U)
2. When using the hand±held tester:
SENSOR CHECK (TEST MODE)
NOTICE:
When having replaced the master cylinder pressure, yaw
rate and deceleration sensors and/or ECU, perform zero
point calibration of the master cylinder pressure, yaw rate
and deceleration sensors (See page DI±897). Make sure
that this operation is done before performing the following.
(a) Procedures for test mode:
(1) Connect the hand±held tester to the DLC3.
(2) Check that the shift lever is in the P position, and
turn the steering wheel to the neutral position.
(3) Start the engine.
(4) Select the SIGNAL CHECK on the hand±held tes-
ter.
(5) Check that the ABS warning light and VSC TRAC
warning light blink.
HINT:
If the ABS and VSC TRAC warning lights do not blink, inspect
the ABS warning light circuit, VSC TRAC warning light circuit
and Ts terminal circuit.
(6) Keep the vehicle in a stationary condition on a level
surface for 4 sec. or more.
ABS warning light circuitDI±1021 or DI±1025
VSC TRAC warning light circuitDI±1027 or DI±1031
Ts terminal circuitDI±1057
(b) Check the yaw rate and deceleration sensor.
Shift the shift lever to the D position and drive the vehicle
at a vehicle speed of approx. 3 mph (5 km/h), turn the
steering wheel either to the left or right for 90° or more,
and turn the vehicle through 180 degrees. Check that the
VSC buzzer sounds for 3 seconds upon start off.
Stop the vehicle and shift the shift lever to the P position,
check that the VSC buzzer sounds again for 3 seconds.

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±903
1097 Author: Date:
2005 SEQUOIA (RM1146U)
HINT:

If the VSC buzzer sounds twice, the sensor check has
been completed normally.

If the VSC buzzer does not sound, check the VSC buzzer
circuit (see page DI±1052), then do the sensor check
again.

Drive the vehicle through 180°. At the end of the turn its
check, the direction of the vehicle should be within 180°
± 5° of its start position.

Do not spin the wheels.

If the buzzer sounds after start off, then the deceleration
sensor check has passed its check. If the buzzer sounds
at the completion of a turn its check, then the yaw rate
sensor check has passed. The buzzer sound should be
heard during the sensor checks.
(c) Check the master cylinder pressure sensor.
(1) Turn the ignition switch to the ON position.
(2) Keep the vehicle in a stationary condition on a level
surface for 2 sec. or more.
(3) Keeping the vehicle in a stationary condition and
not pressing on the brake pedal for 1 sec. or more,
depress the brake pedal with 147 N (15 kgf, 33 lbf)
or more for 2 sec. or more on a new ECU.
NOTICE:
If zero point calibration has never been performed on a new
ECU, master cylinder pressure sensor check cannot be
completed correctly. Perform zero point calibration first
(See page DI±897).
HINT:
At this time, the buzzer sounds for 3 seconds.
(d) Check the speed sensor.
Drive the vehicle straight forward.
When driving the vehicle at the speed of 28 mph (45 km/h)
or higher for several seconds, check that the ABS warn-
ing light goes off.
HINT:
There is a case that the sensor check is not completed if the ve-
hicle has its wheels spun or its steering wheel turned during this
check.
(e) Stop the vehicle.
(f) Read the DTC by following the prompts on the tester
screen.
HINT:
Refer to the hand±held tester operator's manual for further de-
tails.

DI±904
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1098 Author: Date:
2005 SEQUOIA (RM1146U)
3. DTC of ABS sensor check function:
Code No.DiagnosisTrouble Area
C1271 / 71Low output voltage of right front speed sensor

Right front speed sensor

Sensor installation

Sensor rotor
C1272 / 72Low output voltage of left front speed sensor

Left front speed sensor

Sensor installation

Sensor rotor
C1273 / 73Low output voltage of right rear speed sensor

Right rear speed sensor

Sensor installation

Sensor rotor
C1274 / 74Low output voltage of left rear speed sensor

Left rear speed sensor

Sensor installation

Sensor rotor
C1275 / 75Abnormal change in output voltage of right front speed sen-
sorRight front speed sensor rotor
C1276 / 76Abnormal change in output voltage of left front speed sen-
sorLeft front speed sensor rotor
C1277 / 77Abnormal change in output voltage of right rear speed sen-
sorRight rear speed sensor rotor
C1278 / 78Abnormal change in output voltage of left rear speed sensorLeft rear speed sensor rotor
C1279 / 79Deceleration sensor is faulty
Deceleration sensor

Sensor installation
C1281 / 81Master cylinder pressure sensor output signal is faultyMaster cylinder pressure sensor
HINT:
Read the number of blinks of the ABS warning light.
DTC of VSC sensor check function:
Code No.DiagnosisTrouble Area
C0371 / 71Yaw rate sensor output signal malfunction
Yaw rate sensor

Yaw rate sensor circuit
HINT:
Read the number of blinks of the VSC TRAC warning light.

DI93F±04
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±905
1099 Author: Date:
2005 SEQUOIA (RM1146U)
PROBLEM SYMPTOMS TABLE
If a normal code is indicated during the DTC check but the problem still occurs, check the circuits for each
problem symptom in the order given in the table below and proceed to the relevant troubleshooting page.
NOTICE:

When replacing the skid control ECU, sensor, etc., turn the ignition switch OFF.

When replacing the master cylinder pressure, yaw rate and deceleration sensors and/or the
ECU, make sure to perform master cylinder pressure, yaw rate, and deceleration sensors' zero
point calibration (See page DI±897).
SymptomSuspected AreaSee page
ABS does not operate
When the following 1. to 4. are all normal and the problem
is still occurring, replace the skid control ECU.
1. Check the DTC reconfirming that the normal code is
output.
2. IG power source circuit
3. Speed sensor circuit
4. Check the hydraulic circuit for leakage.
DI±911
DI±957
DI±925
DI±1059
ABS does not operate efficiently
When the following 1. to 4. are all normal and the problem
is still occurring, replace the skid control ECU.
1. Check the DTC reconfirming that the normal code is
output.
2. Speed sensor circuit
3. Stop light switch circuit
4. Check the hydraulic circuit for leakage.
DI±911
DI±925
DI±963
DI±1059
ABS warning light abnormal
1. ABS warning light circuit
2. Skid control ECUDI±1021 or
DI±1025
BRAKE warning light abnormal
1. BRAKE warning light circuit
2. Skid control ECU
3. Translate ECUDI±1033 or
DI±1038
DTC check cannot be done
When the following 1. to 3. are all normal and the problem
is still occurring, replace the skid control ECU.
1. ABS warning light circuit
2. Tc terminal circuit
3. VSC TRAC warning light circuit
DI±1021 or
DI±1025
DI±1055
DI±1027
DI±1031
Speed sensor signal check cannot be done1. Ts terminal circuit
2. Skid control ECUDI±1057
TRAC does not operate
Only when 1. to 4. are all normal and the problem is still
occurring, replace the skid control ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. IG power source circuit
3. Check the hydraulic circuit for leakage
4. Speed sensor circuit
DI±911
DI±957
DI±1059
DI±925
TRAC does not operate efficiently
Only when 1. to 3. are all normal and the problem is still
occurring, replace the skid control ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. Check the hydraulic circuit for leakage
3. Speed sensor circuit
DI±911
DI±1059
DI±925

DI±906
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1100 Author: Date:
2005 SEQUOIA (RM1146U) VSC does not operate
Only when 1. to 9. are all normal and the problem is still
occurring, replace the skid control ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. Perform zero point calibration
3. IG power source circuit
4. Check the hydraulic circuit for leakage
5. Speed sensor circuit
6. Deceleration sensor circuit
7. Yaw rate sensor circuit
8. Steering angle sensor circuit
9. Master cylinder pressure sensor circuit
DI±911
DI±897
DI±957
DI±1059
DI±925
DI±951
DI±954
DI±946
DI±983
VSC does not operate efficiently
Only when 1. to 8. are all normal and the problem is still
occurring, replace the skid control ECU.
1. Check the DTC, reconfirming that the normal code is
output.
2. Perform zero point calibration
3. Check the hydraulic circuit for leakage
4. Speed sensor circuit
5. Deceleration sensor circuit
6. Yaw rate sensor circuit
7. Steering angle sensor circuit
8. Master cylinder pressure sensor circuit
DI±911
DI±897
DI±1059
DI±925
DI±951
DI±954
DI±946
DI±983
VSC TRAC warning light abnormal
1. VSC TRAC warning light circuit
2. Skid control ECUDI±1027 or
DI±1031
SLIP indicator light abnormal
1. SLIP indicator light circuit
2. Skid control ECUDI±1041 or
DI±1045
VSC OFF (TRAC OFF) indicator abnormal
1. VSC OFF (TRAC OFF) indicator light circuit
2. VSC OFF (TRAC OFF) switch circuit
3. Skid control ECUDI±1048

DIDM0±01
F16974
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±907
1101 Author: Date:
2005 SEQUOIA (RM1146U)
TERMINALS OF ECU
1. Skid Control ECU:
Symbols (Terminal No.)Terminal Description
GND (1)Skid control ECU ground
CANL (2)Vehicle CAN communication line
VCP (3)Pedal stroke sensor (Delta S Sensor) line
CANH (6)Vehicle CAN communication line
E3 (8)Pedal stroke sensor (Delta S Sensor) ground
VYS (11)Yaw rate sensor power source
IG1 (13)IG1 power supply
PIM (14)Pedal stroke sensor (Delta S Sensor) line
D/G (15)Diagnosis tester communication line
+BM (16)Motor relay power supply
BST (17)Brake booster line
PSNC (18)Brake booster line
SS1 (19)Yaw rate sensor signal line
STS (20)Brake booster line
PSNO (21)Brake booster line
BZ (22)Buzzer output
SS2 (23)Yaw rate sensor signal line
GYAW (24)Yaw rate sensor ground
PMC2 (25)M/C pressure sensor 2 signal
VCM2 (26)M/C pressure sensor 2 power supply
E2 (27)M/C pressure sensor 2 ground
PMC (28)M/C pressure sensor 1 signal
E1 (29)M/C pressure sensor 1 ground
VCM (30)M/C pressure sensor 1 power supply
BSTP (31)Brake booster line
GND2 (32)Skid control ECU ground
FL+ (33)FL wheel speed signal line
FL± (34)FL wheel speed signal line
WA (35)ABS warning light output
RR± (36)RR wheel speed signal line
RR+ (37)RR wheel speed signal line
BSW (38)Brake inhibit signal line
STP (39)Stop light switch signal input