2001 TOYOTA SEQUOIA Page 18

DI±936
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1130 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1201 / 51 Engine Control System Malfunction
CIRCUIT DESCRIPTION
If trouble occurs in the engine control system, the ECM transmits the abnormality to the skid control ECU
via translate ECU. The skid control ECU sets this DTC and the skid control ECU prohibits TRAC and VSC
control.
DTC No.DTC Detecting ConditionTrouble Area
C1201 / 51
Conditions 1. and 2. continue for 5 sec.:
1. Engine speed: 500 rpm or more.
2. A trouble signal of the engine control system is input.

Engine control system
INSPECTION PROCEDURE
1 Check engine control system.
CHECK:
Check engine control system (See page DI±43).
RESULT:
DTC is not outputA
DTC is outputB
B Check and repair engine control system
(See page DI±9).
A
Replace ECM (See page SF±80).
DIDM6±01

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±939
1133 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check brake fluid level.
CHECK:
Check the amount of fluid in the brake reservoir.
NG Check and repair brake fluid leakage and add
fluid.
OK
2 Check DTC of translate ECU (translate DTC 58).
CHECK:
Check DTC of the translate ECU (See page DI±911).
RESULT:
DTC 58 is not outputA
DTC 58 is outputB
B Go to step 4.
A
3 Check for open and short circuit in harness and connector between skid control
ECU and translate ECU (CAN1 circuit).
NG Repair or replace harness or connector
(CAN1 circuit).
OK
Replace skid control ECU
(See page BR±52).
NOTICE:
When replacing the skid control ECU, perform zero point calibration (See page DI±897).

F18069
DI±940
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1134 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check brake fluid level warning switch.
PREPARATION:
Disconnect the brake fluid level warning switch connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Tester ConnectionSwitch ConditionSpecified Condition
(B2±1) ± (B2±2)Float UP10 kW or more
(No continuity)
(B2±1) ± (B2±2)Float DOWN1 W or less (Continuity)
NG Replace brake reservoir tank.
OK
5 Check for open and short circuit in harness and connector between brake fluid
level warning switch and translate ECU (See page IN±35).
NG Repair or replace harness or connector.
OK

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±941
1135 Author: Date:
2005 SEQUOIA (RM1146U)
6 Replace the translate ECU and check if trouble occurs again.
PREPARATION:
(a) Clear the DTC (See page DI±911).
(b) Turn the ignition switch OFF.
CHECK:
Turn the ignition switch to the ON position, and check if the same DTC still remains in the memory.
RESULT:
DTC C1202/52 is outputA
DTC C1202/52 is not outputB
B END
A
Replace skid control ECU
(See page BR±52).
NOTICE:
When replacing the skid control ECU, perform zero point calibration (See page DI±897).

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±943
1137 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check engine control system.
CHECK:
Check engine control system (See page DI±43).
RESULT:
DTC is not outputA
DTC is outputB
B Repair engine control system according to the
output code (See page DI±58).
A
2 Check DTC of translate ECU.
CHECK:
Check DTC of the translate ECU (See page DI±911).
RESULT:
DTC is output (53, 65, 94)A
DTC is not outputB
B Go to step 4.
A
3 Check for open and short circuit in harness and connector between skid control
ECU and translate ECU (CAN1 circuit).
NG Repair or replace harness or connector
(CAN1 circuit).
OK

DI±944
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1138 Author: Date:
2005 SEQUOIA (RM1146U)
4 Replace the translate ECU and check if trouble occurs again.
PREPARATION:
(a) Clear the DTC (See page DI±911).
(b) Turn the ignition switch OFF.
CHECK:
Turn the ignition switch to the ON position, and check if the same DTC still remains in the memory.
RESULT:
DTC is outputA
DTC is not outputB
B END
A
Replace skid control ECU
(See page BR±52).
NOTICE:
When replacing the skid control ECU, perform zero point calibration (See page DI±897).

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±945
1139 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1223 / 43 Malfunction in ABS Control System
CIRCUIT DESCRIPTION
HINT:
This DTC is output when the VSC system detects a malfunction in the ABS system.
DTC No.DTC Detecting ConditionTrouble Area
C1223 / 43ABS control system is abnormal.ABS control system
INSPECTION PROCEDURE
1 Check DTC (See page DI±911).
PREPARATION:
(a) Clear the DTC.
(b) Turn the ignition switch OFF.
CHECK:
Turn the ignition switch to the ON position, and check if the same DTC still remains in the memory.
RESULT:
DTC is outputA
DTC is not outputB
B No problem.
A
Repair circuit indicated by output code
(See page DI±921).
DI93K±03

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±949
1143 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check for open and short circuit in harness and connector between steering
angle sensor and translate ECU (See page IN±35).
NG Repair or replace harness or connector.
OK
4 Check for open and short circuit in harness and connector between skid control
ECU and translate ECU (CAN1 circuit).
NG Repair or replace harness or connector
(CAN1 circuit).
OK
5 Is DTC still output?
Check DTC on page DI±911.
NO No problem.
YES