2001 TOYOTA SEQUOIA ECU

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

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

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

DIDM2±01
F09750
CG TcDLC3
R01346
Normal System Code
0.25 sec.
0.25 sec. 2 sec.
ON
OFF
ON
OFF0.5 sec. 0.5 sec.
Codes 11 and 21
4 sec.1.5 sec.
2.5 sec.
Code 11 Code 21
F09750
CG TcDLC3
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±911
1105 Author: Date:
2005 SEQUOIA (RM1146U)
DTC CHECK / CLEAR
USING SST (CHECK WIRE):
1. CHECK DTC
(a) Using SST, connect terminals Tc and CG of the DLC3.
SST 09843±18040
(b) Turn the ignition switch to the ON position.
(c) Read the DTC from the ABS and VSC TRAC warning
lights on the combination meter.
HINT:

If no code appears, inspect the diagnostic circuit, ABS
warning light circuit or VSC TRAC warning light circuit.
Trouble AreaSee page
Tc terminal circuitDI±1055
ABS warning light circuitDI±1021 or
DI±1025
VSC TRAC warning light circuitDI±1027 or
DI±1031

As examples, the blinking patterns for normal system
code and codes 11 and 21 are shown on the left.
(1) Codes are explained in the code table on page
DI±921.
(2) After completing the check, disconnect terminals Tc
and CG of the DLC3, and turn off the display.
If 2 or more trouble codes are identified at the same time, the
DTCs will be displayed in ascending order.
2. CHECK TRANSLATE DTC
HINT:
Once the ignition switch is turned off, all DTCs in the translate
ECU are cleared.
(a) Release the parking brake pedal.
(b) Check the brake fluid level.
(c) Using SST, connect terminals Tc and CG of the DLC3.
SST 09843±18040
(d) Read the DTC of the BRAKE warning light.
NOTICE:
When reading DTCs, be sure to be seated in the driver's
seat and depressing the brake pedal.

F09750
CG TcDLC3
BR3890
D05981
Hand±held
Tester
DLC3
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±913
1107 Author: Date:
2005 SEQUOIA (RM1146U)
USING SST (CHECK WIRE):
4. CLEAR DTC
(a) Using SST, connect terminals Tc and CG of the DLC3.
SST 09843±18040
(b) Turn the ignition switch to the ON position.
(c) Clear the DTC stored in the ECU by depressing the brake
pedal 8 times or more within 5 seconds.
(d) Check that the warning light indicates the normal code.
(e) Remove the SST from the terminals of the DLC3.
SST 09843±18040
HINT:
Cancellation cannot be done by removing the battery cable or
ECU±IG fuse.
USING HAND±HELD TESTER:
5. CLEAR DTC
(a) Hook up the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Operate the hand±held tester to erase the codes.
HINT:
(d) Please refer to the hand±held tester operator's manual
for further details.

DIDM3±01
DI±914
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1108 Author: Date:
2005 SEQUOIA (RM1146U)
FREEZE FRAME DATA
1. FREEZE FRAME DATA
HINT:

Whenever a DTC is detected or the ABS operates, the skid control ECU stores the current vehicle (sen-
sor) state as freeze frame data.

The skid control ECU stores the number of times (maximum: 31) the ignition switch has been turned
from off to the ON position since the last time the ABS was activated. However, if the vehicle was
stopped or at low speed (4.3 mph (7 km/h) or less), or if a DTC is detected, the skid control ECU will
not count the number since then.

Freeze frame data at the time the ABS operates:
The skid control ECU stores and updates data whenever the ABS system operates.
When the ECU stores data at the time a DTC is detected, the data stored when the ABS operated is
erased.

Freeze frame data at the time a DTC is detected:
When the skid control ECU stores data at the time a DTC is detected, no updates will be performed
until the data is cleared.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) From the display on the tester, select the ºFREEZE FRAME DATAº.
Hand±held Tester DisplayMeasurement ItemReference Value
VEHICLE SPDWheel speed sensor readingmin.: 0 km/h
max.: 326 km/h
STOP LIGHT SWStop light switch signalStop light switch ON: ON, OFF: OFF
# IG ONNumber of operations of ignition switch ON after
memorizing freeze frame data0 to 31
MAS CYL PRESSMaster cylinder pressure sensor readingBrake pedal released: 0.3 to 0.9 V
Brake pedal depressed: 0.8 to 4.5 V
MASS PRESS GRADEMaster cylinder pressure sensor change±30 to 255 MPa/s
SYSTEMSystem status
ABS activated: ABS
VSC/TRC activated: VSC/TRC
BA activated: BA
Fail safe mode activated: FAIL SF
No system activated: NO SYS
YAW R AT EYaw rate angle sensor reading±128 to 127
STEERING ANGSteering sensor readingLeft turn: Increase
Right turn: Drop
THROTTLETh ttl iti diRelease accelerator pedal: Approx. 0 deg.THROTTLEThrottle position sensor readingRelease accelerator edal: A rox. 0 deg.
Depress accelerator pedal: Approx. 125 deg.
G (RIGHT & LEFT)Right and left G±1.869 to 1.869
G (BACK & FORTH)Back and forth G±1.869 to 1.869
VSC / TRC OFF SWVSC OFF switch signalTRAC OFF SW ON: ON
OFF: OFF
SHIFT POSITIONShift lever position
FAIL
P, N
R
D
4
3
2
L
TROUBLE CODEFreeze DTCmin.: 0
max.: 255