Page 1105 of 4323

± 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.
Page 1106 of 4323

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 faultyDeceleration 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 malfunctionYaw rate sensor
Yaw rate sensor circuit
HINT:
Read the number of blinks of the VSC TRAC warning light.
Page 1107 of 4323

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
Page 1108 of 4323

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
Page 1109 of 4323

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
Page 1110 of 4323

F19198
Skid Control ECU
(harness side connector) DI±908
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1102 Author: Date:
2005 SEQUOIA (RM1146U)Symbols (Terminal No.) Terminal Description
TS (40)Sensor check input
+BO (41)Steering angle sensor line
RL+ (42)RL wheel speed signal line
RL± (43)RL wheel speed signal line
VSCW (44)VSC OFF indicator output
FR± (45)FR wheel speed signal line
FR+ (46)FR wheel speed signal line
+BS (47)Solenoid relay power supply
2. Terminal Inspection
Disconnect the connector and measure the voltage on the wire harness side.
HINT:
Voltage can not be measured with the connector connected to the skid control ECU as the connector is water
resistance.
Symbols (Terminal No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
+BM (16) ± GND1, 2 (1, 32)B±R ± W±BMotor relay power supplyIG switch ON10 to 14 V
GYAW (24) ± GND1, 2 (1, 32)G ± W±BYaw rate sensor groundAlwaysBelow 1 W
E3 (8) ± GND1, 2 (1, 32)L ± W±BM/C pressure sensor 3
groundAlwaysBelow 1 W
E2 (27) ± GND1, 2 (1, 32)W ± W±BM/C pressure sensor 2
groundAlwaysBelow 1 W
E1 (29) ± GND1, 2 (1, 32)W ± W±BM/C pressure sensor 1
groundAlwaysBelow 1 W
STP (39) ± GND1, 2 (1, 32)G±Y ± W±BStop light switch signal in-
putBrake pedal depressed8 to 14 V
STP (39) ± GND1, 2 (1, 32)G±Y ± W±BStop light switch signal in-
putBrake pedal releasedBelow 1.5 V
+BS (47) ± GND1, 2 (1, 32)B±R ± W±BSolenoid relay power sup-
plyIG switch ON10 to 14 V
Page 1111 of 4323

F16975
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±909
1103 Author: Date:
2005 SEQUOIA (RM1146U)
Translate ECU:
Symbols (Terminal No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
IG1 (1) ± GND (40)B±R ± OTranslate ECU power
supplyIG SW ON10 to 14 V
PKB2 (4) ± GND (40)LG±R ± OPKB signal lineIG SW ON, PKB SW ONBelow 2.0 V
PKB2 (4) ± GND (40)LG±R ± OPKB signal lineIG SW ON, PKB SW OFF10 to 14 V
VSC+ (7) ± VSC± (11)L ± WCAN communication lineIG switch ONPulse generation
ENG+ (14) ± ENG± (16)R ± WECM communicationIG SW ONPulse generation
SS1+ (18) ± SS1± (19)O ± YSteering angle sensor lineIG SW ONPulse generation
TRIG (20) ± GND (40)W±L ± OSteering angle sensor sig-
nalIG SW ON4.5 to 5.5 V
LVL2 (24) ± GND (40)Y±L ± OBrake fluid level signalBrake fluid level SW ONBelow 1.5 V
CSW (26)* ± GND (40)L±W ± OCenter diff. lock SW sig-
nalIG SW ON, VSC OFF SW ONBelow 1.5 V
CSW (26)* ± GND (40)L±W ± OCenter diff. lock SW sig-
nalIG SW ON, VSC OFF SW OFF8 to 14 V
TS (27) ± GND (40)R±L ± OSensor check inputIG switch ON10 to 14 V
TC (28) ± GND (40)P±B ± ODiagnosis tester commu-
nication lineIG switch ON10 to 14 V
CD (29)* ± GND (40)BR±Y ± OCenter diff. lock lamp sig-
nalIG SW ON, center diff. lock indica-
tor ONBelow 1.5 V
CD (29)* ± GND (40)BR±Y ± OCenter diff. lock lamp sig-
nalIG SW ON, center diff. lock indica-
tor OFF8 to 14 V
EXI2 (31)* ± GND (40)Y±G ± OCenter diff. lock signalIG SW ON, center diff. lock SW ONBelow 1.5 V
EXI2 (31)* ± GND (40)Y±G ± OCenter diff. lock signalIG SW ON, center diff. lock SW
OFF8 to 14 V
IND (37) ± GND (40)W±R ± OSLIP indicator signalIG SW ON, SLIP indicator ONBelow 2.0 V
IND (37) ± GND (40)W±R ± OSLIP indicator signalIG SW ON, SLIP indicator OFF10 to 14 V
WT (38) ± GND (40)R±G ± OVSC OFF or TRAC OFF
warning light circuitIG SW ON, VSC OFF or TRAC
OFF warning light ONBelow 2.0 V
WT (38) ± GND (40)R±G ± OVSC OFF or TRAC OFF
warning light circuitIG SW ON, VSC OFF or TRAC
OFF warning light OFF10 to 14 V
BRL (39) ± GND (40)R±B ± OBRAKE warning light cir-
cuitIG SW ON, BRAKE warning light
ONBelow 2.0 V
BRL (39) ± GND (40)R±B ± OBRAKE warning light cir-
cuitIG SW ON, BRAKE warning light
OFF10 to 14 V
*: Only for 4WD
Page 1112 of 4323

DIDM1±01
F13444
USA: CANADA:USA: CANADA:2WD: 4WD:
DI±910
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1104 Author: Date:
2005 SEQUOIA (RM1146U)
DIAGNOSIS SYSTEM
1. CHECK WARNING LIGHT
(a) Release the parking brake pedal.
(b) When the ignition switch is turned ON, check that the ABS
warning light, VSC TRAC warning light, VSC OFF (TRAC
OFF) indicator light, BRAKE warning light and SLIP indi-
cator light come on for approx. 3 seconds.
HINT:
When the parking brake is applied or the level of the brake
fluid is low, the BRAKE warning light comes on.
If the indicator check result is not normal, proceed to trou-
bleshooting for the ABS warning light circuit, VSC TRAC
warning light circuit, VSC OFF (TRAC OFF) indicator light
circuit, BRAKE warning light circuit or SLIP indicator light
circuit.
Trouble AreaSee page
ABS warning light circuitDI±1021 or
DI±1025
VSC TRAC warning light circuitDI±1027 or
DI±1031
VSC OFF (TRAC OFF) indicator light circuitDI±1048
BRAKE warning light circuitDI±1033 or
DI±1038
SLIP indicator light circuitDI±1041 or
DI±1045
The DTCs are simultaneously stored in the memory. The
DTCs can be read by connecting the SST between TC
and CG terminals of the DLC3 and observing the blinking
of the ABS and VSC warning lights, or by connecting a
hand±held tester.
This system has a sensor signal check function (TEST
MODE) (See page DI±899).
The DTC can be read by connecting the SST between ter-
minals TS and CG of the DLC3 and observing the blinking
of the ABS and VSC TRAC warning lights, or by connect-
ing a hand±held tester.