brake fluid TOYOTA SEQUOIA 2001 Service Owner's Manual

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±937
1131 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1202 / 52 Brake Fluid Warning Switch Circuit
CIRCUIT DESCRIPTION
The brake fluid level warning switch sends the appropriate signal to the skid control ECU when the brake
fluid level drops.
A brake fluid level signal is transmitted from the translate ECU to the skid control ECU.
DTC No.DTC Detecting ConditionTrouble Area
C1202 / 52
When any of the following conditions are detected:
1. Low fluid level condition in the brake master cylinder
reservoir tank continues for 30 sec. or more when ve-
hicle stops, or for 60 sec. or more when driving.
2. With ECU terminal IG1 voltage is 9.5 V to 17.2 V and
open circuit for the brake fluid level warning switch cir-
cuit continues for 2 sec. or more.
Brake fluid level

Brake fluid level warning switch

Brake fluid level warning switch circuit

Skid control ECU

CAN1 communication system

Translate ECU
DIDM7±01

F19769
Translate ECU
VSC+
VSC±
IG17
T5
T511
1
T5B±RL
W
AA
J37
J38
A
J37B±R J/C
B±R B±RL
W 7
IL2
6
IL2
1
IL16
S1
2
S1
13
S1 ABS &VSC Actuator
(Skid Control ECU)
CANH
CANL
IG1
8
3C8
3A
B±R Instrument Panel J/B
4
1C
2
1C
3
1C
6
1C4
1F
11
1H
7
1J
1
1L ECU±IG
IGN1
AM1 B±R B±Y
W±R
W±LB±O
W±R
W
1 2Combination Meter
24
C6
Brake
1C5 W
8
ALTF10 Fusible
Link BlockEngine Room J/B
A W±R 1
2D1
2C
4
5
R±B R±B
B1 Brake Fluid Level
Warning SW
Y±L Y±LW±B 23
IA1
129
IA5O
A
A O
OJ43
J/C
IG Sub J/B No.4
LG±R
LG±R 4
4B4
4D
1P2 Parking
Brake SW
B
Battery 39
T5
24
T5
40
T5
4
T5 BRL
LVL2
GND
PKB2Sub J/B No.3
I18
Ignition SW
AM1 IG1
AM2 IG2 1
5 W±L
2
6
AM2
BB±R (CAN1 Circuit)
(CAN1 Circuit) DI±938
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1132 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM

± 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

DI±984
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1178 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Is pedal lowered or spongy?
YES Bleed air from the system (See page BR±4).
NO
2 Check output value of the master cylinder pressure sensor No. 1 and No. 2.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position, and push the hand±held tester main switch ON.
(c) Select DATA LIST mode on the hand±held tester.
CHECK:
Check that the brake fluid pressure value of the master cylinder pressure sensor displayed on the hand±held
tester changes when depressing the brake pedal.
ItemMeasurement Item /
Range (Display)Normal ConditionDiagnostic Note
MAS CYL PRS 1
Master cylinder pressure
sensor 1 reading / min.: 0
V, max.: 5 VWhen brake pedal is re-
leased : 0.3 to 0.9 VReading increases when
brake pedal is depressed
MAS CYL PRS 2
Master cylinder pressure
sensor 1 reading / min.: 0
V, max.: 5 VWhen brake pedal is re-
leased : 0.3 to 0.9 VReading increases when
brake pedal is depressed
OK:
Brake fluid pressure value changes.
OK Go to step 4.
NG
3 Check for open and short circuit in harness and connector between master cyl-
inder pressure sensor and skid control ECU (See page IN±35).
NG Repair or replace harness or connector.
OK

F19197
S1 ABS & VSC Actuator
(Skid Control ECU)Translate
ECU
CANH
CANL6
2L
WL
W 7
IL2
6
IL27
T5
11
T5VSC+
VSC±
IG1 1
T5 B±R
J37 J37J/C
B±R
B±R8
3C 8
3A
I18
Ignition SW
4
1F4
1C
1L6
1C ECU±IG
AM1
AM1 IG1
B±Y
2
W±L W
ALT
Battery24
T5
40
T5LVL2
GND 23
IA1 9
IA5Y±L Y±L W±B O
A
O A
AB1
Brake Fluid
Level Warning SW
J43
J/C
IG 1Sub J/B No.3
Instrument Panel J/B
8
5F10
Fusible Link Block
B1
1 2
2A
A
1
(*) CAN1 Circuit (*)(*)
(*)
(*) DI±1002
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1196 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 58 Malfunction of Brake Fluid Level Warning
Switch
CIRCUIT DESCRIPTION
The brake fluid level warning switch sends the appropriate signal to the translate ECU.
This signal indicates a drop in brake fluid level.
DTC No.DTC Detecting ConditionTrouble Area
58

Brake fluid level warning switch connector is disconnected
for 1 sec. or more.

Brake fluid level warning switch is ON for 30 sec. or more.
Brake fluid level warning switch circuit

Brake fluid level warning switch

Brake fluid reservoir level

Translate ECU
WIRING DIAGRAM
DIDMI±01

F18069
P2
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±1003
1197 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check the DTC of the VSC (See page DI±911).
CHECK:
Check skid control ECU DTC.
RESULT:
DTC is not outputA
DTC (C1202 / 52) is outputB
B Repair circuit indicated by the output code
(See page DI±921).
A
2 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 fluid level warning switch.
OK
3 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±1013
1207 Author: Date:
2005 SEQUOIA (RM1146U)
DTC Normal Code Malfunction in Translate ECU
CIRCUIT DESCRIPTION
If any trouble occurs in the engine control system, the skid control ECU prohibits ABS & VSC control.
DTC No.DTC Detecting ConditionTrouble Area
Normal Code
Conditions 1., 2. or 3. continue for 5 sec. or more:
1. Engine malfunction signal is sent from ECM.
2. Shift malfunction signal is sent from ECM.
3. The shift position is other than P and N, and P range
input voltage is 8 V or more.

ECM circuit

ECM

Brake fluid level

Brake fluid level warning switch circuit

Steering angle sensor

Translate ECU

Skid control ECU

Vehicle CAN

VSC+, VSC± circuit (CAN1 communication system)
INSPECTION PROCEDURE
1 Is DTC output for ECM?
Check DTC on page DI±43.
YES Repair engine control system according to the
output code (See page DI±58).
NO
2 Check the DTC of the ABS and VSC (See page DI±911).
CHECK:
Check skid control ECU DTC.
RESULT:
Only DTC ºC1203/53º of the VSC system is outputA
Except DTC ºC1203/53º of the VSC system are outputB
B Repair ABS and VSC control system according
to the code output (See page DI±921).
A
DI6OF±12

± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±1033
1227 Author: Date:
2005 SEQUOIA (RM1146U)
BRAKE Warning Light Circuit (Remains ON)
CIRCUIT DESCRIPTION
The BRAKE warning light comes on when the brake fluid is insufficient, the parking brake is applied or the
EBD is defective.
The skid control ECU is connected to the translate ECU via the CAN1 communication system.
DIDMN±01

F19769
Translate ECU
VSC+
VSC±
IG17
T5
T511
1
T5B±RL
W
AA
J37
J38
A
J37B±R J/C
B±R B±RL
W 7
IL2
6
IL2
1
IL16
S1
2
S1
13
S1 ABS &VSC Actuator
(Skid Control ECU)
CANH
CANL
IG1
8
3C8
3A
B±R Instrument Panel J/B
4
1C
2
1C
3
1C
6
1C4
1F
11
1H
7
1J
1
1L ECU±IG
IGN1
AM1 B±R B±Y
W±R
W±LB±O
W±R
W
1 2Combination Meter
24
C6
Brake
1C5 W
8
ALTF10 Fusible
Link BlockEngine Room J/B
A W±R 1
2D1
2C
4
5
R±B R±B
B1 Brake Fluid Level
Warning SW
Y±L Y±LW±B 23
IA1
129
IA5O
A
A O
OJ43
J/C
IG Sub J/B No.4
LG±R
LG±R 4
4B4
4D
1P2 Parking
Brake SW
B
Battery 39
T5
24
T5
40
T5
4
T5 BRL
LVL2
GND
PKB2Sub J/B No.3
I18
Ignition SW
AM1 IG1
AM2 IG2 1
5 W±L
2
6
AM2
BB±R (*) CAN1 Circuit
(*)
(*)
(*) (*) DI±1034
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
1228 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM