check engine TOYOTA SEQUOIA 2001 Service Repair Manual

F16807
GND
F19430
GND
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±719
913 Author: Date:
2005 SEQUOIA (RM1146U) RM+ (S25±20) ±
GND (S25±22)
R±L ± W±B
Height Control
Compressor
Motor Lock (+)Engine idling, vehicle height changes from ºNORMALº to
ºHIGHº by pressing the height control switch (While
height control compressor assy is working).
Below 1.0 V
RM± (S25±21) ±
Body groundBR±Y ± W±B
Height Control
Compressor
Motor Lock (±)
AlwaysBelow 1.0 V
GND (S25±22) ±
Body groundW±B ±
Body groundGroundAlwaysBelow 1.0 V
B (S25±24) ±
GND (S25±22)V ± W±BBatteryIG switch ON10 to 14 V
LO (S25±26) ± PWB
Height Control
I di t ºLOº
Engine idling, vehicle height is ºNORMALº "
P i th ºDOWNº b tt f th h i ht t l it h10 V or more "LO (S25 26)
GND (S25±22)P ± W±BIndicator ºLOº
SignalPressing the ºDOWNº button of the height control switch
turns on the ºLOº indicator lamp (*1)10 V or more "
Below 5 V
STP (S25±27) ± GY WBStop LightBk dld dRl d10 to 14 V "STP (S25 27)
GND (S25±22)G±Y ± W±BSto Light
SwitchBrake pedal depressed " Released10 to 14 V "
Below 1.5 V
SIL (S25±30) ±
GND (S25±22)G±R ± W±BDiagnosis Sig-
nalHand±held tester is connected to DLC3Pulse generation
(See waveform 3)
DOOR (S25±31) ± RWBDSilIG switch ON, each door opened "Below 1.5 VDOOR (S25 31)
GND (S25±22)R ± W±BDoor SignalIG switch ON, each door o ened "
All door closed
Below 1.5 V
10 to 14 V
DNSW (S25±32) ±
GND (S25±22)W ± W±B
Height Control
Switch
ºDOWNº SignalIG switch ON, ºDOWNº button of height control switch
pushed in "
ºDOWNº button of height control switch releasedBelow 1.5 V "
10 to 14 V
BAT (S25±25) ±
GND (S25±22)V ± W±BBatteryAlways10 to 14 V
CANL (S25±28) ±
GND (S25±22)W ± W±BCAN Commu-
nication SignalIG switch ONPulse generation
(See waveform 1)
CANH (S25±29) ±
GND (S25±22)G ± W±BCAN Commu-
nication SignalIG switch ONPulse generation
(See waveform 2)
*1: Perform inspection after checking that the height control indicator lamp switches are illuminated when
the height control switch button is pressed.
Waveform 1 (Reference):
ItemContents
TerminalCANL ± GND
Tool setting1V/DIV, 10ms/DIV
Vehicle conditionIgnition SW ON, Engine stopped
Waveform 2 (Reference):
ItemContents
TerminalCANH ± GND
Tool setting1V/DIV, 10ms/DIV
Vehicle conditionIgnition SW ON, Engine stopped

F19458
DI±750
± DIAGNOSTICSAIR SUSPENSION SYSTEM
944 Author: Date:
2005 SEQUOIA (RM1146U)
2 Inspect AIR SUS relay.
PREPARATION:
Remove the AIR SUS relay from the engine room R/B No. 2.
CHECK:
Check continuity between each terminal of the AIR SUS relay.
OK:
Tester connectionResistance
3 ± 510 kW or higher
3 ± 5
Below 1 W
(When battery voltage is applied to ter-
minals 1±2)
NG Replace AIR SUS relay.
OK

F16805
S25
Suspension Control ECU
Wire Harness View:
RC
F19460
Engine Room R/B No. 2:
AIR SUS
Relay Terminal
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±751
945 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check harness and connector (Engine room R/B ± Suspension control ECU,
Body ground).
PREPARATION:
Disconnect the ECU connector.
CHECK:
Check for an open or short circuit in the harness and the con-
nector between the AIR SUS relay terminal 1 of the engine
room R/B and terminal S25±5 (RC) of the suspension control
ECU.
OK:
There is no open or short in the wire harness.
CHECK:
Check for an open circuit in the harness and the connector be-
tween the AIR SUS relay terminal 2 of the engine room R/B and
body ground.
OK:
There is no open in the wire harness.
NG Repair or replace harness or connector.
OK
Replace suspension control ECU
(See page IN±35).

F19461
Height Control Compressor
Connector Front View:
H13
DI±756
± DIAGNOSTICSAIR SUSPENSION SYSTEM
950 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check harness and connector (Height control compressor ± Battery, Body
ground).
PREPARATION:
(a) Reconnect the ECU connector.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Tester connectionConditionSpecified value
H13±1 ± Body ground
Engine idling, height con-
trol switch is pushed from
ºNº to ºUPº
10 to 14 V
HINT:
Measure the voltage within 90 seconds.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Tester connectionConditionSpecified value
H13±2 ± Body groundAlwaysBelow 1 W
NG Repair or replace harness or connector.
OK
Replace suspension control ECU
(See page IN±35).

F16805
S25
BAT
B
Wire Harness View:
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±765
959 Author: Date:
2005 SEQUOIA (RM1146U)
A
3 Inspect fuse (AIR SUS No. 2).
PREPARATION:
Remove the AIR SUS No. 2 fuse from the engine room R/B.
CHECK:
Check continuity of the AIR SUS No. 2 fuse.
OK:
Continuity
NG Inspect for short circuit in all harness and com-
ponents connected to AIR SUS No. 2 fuse.
OK
4 Inspect suspension control ECU.
PREPARATION:
Disconnect the ECU connector.
CHECK:
Measure the voltage between terminal S25±24 (B) of the sus-
pension control ECU connector and body ground and between
terminal S25±25 (BAT) and body ground.
OK:
Voltage: 10 to 14 V
NG Repair or replace harness or connector.
OK

DIDLY±01
F09750
DLC3
Ts
Tc
CG
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±897
1091 Author: Date:
2005 SEQUOIA (RM1146U)
CALIBRATION
1. ZERO POINT CALIBRATION OF MASTER CYLINDER
PRESSURE, YAW RATE AND DECELERATION SEN-
SORS
HINT:
When having replaced the master cylinder pressure, yaw rate
and deceleration sensors and/or the ECU, make sure to per-
form master cylinder pressure, yaw rate and deceleration sen-
sors' zero point calibration.
NOTICE:

While obtaining the zero point, do not vibrate the ve-
hicle by tilting, moving or shaking it and keep it in a
stationary condition. (Do not start the engine.)

Be sure to do this on a level surface (within an inclina-
tion of 1 degree).
(a) Perform master cylinder pressure, yaw rate and decelera-
tion sensors zero point calibration.
(1) Using SST, connect terminals Ts and CG of the
DLC3.
SST 09843±18040
(2) Shift the shift lever to the P position.
(3) Turn the ignition switch to the ON position.
(4) Keep the vehicle in a stationary condition on a level
surface for 4 sec. or more.
(5) Keep your foot off the brake pedal.
Do not leave 4WD vehicles in the L4 position.
(6) Press the center diff. lock (TRAC OFF) switch 3
times within 3 seconds.
(7) Check that the VSC buzzer sounds for 3 seconds.
HINT:

If the VSC buzzer does not sound, do the zero point cal-
ibration again and/or check the VSC buzzer circuit (See
page DI±1052).

If the VSC buzzer does not sound, check for yaw rate and
deceleration sensor failure (See page DI±911).
(8) Turn the ignition switch OFF.
(9) Disconnect terminals Ts and CG of the DLC3.
(b) Perform steering angle sensor zero point calibration.
This calibration is carried out automatically by following
procedures below:
(1) Make sure the system is not in sensor check mode.
(2) Calibrate the steering angle sensor by driving the
vehicle in a straight line at more than 7 MPH (12
km/h) for 5 seconds.

DIDLZ±01
F09750
DLC3Ts
CG
BR3904
0.13 sec. 0.13 sec.
ON
OFF
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI±899
1093 Author: Date:
2005 SEQUOIA (RM1146U)
TEST MODE PROCEDURE
1. When not using the hand±held tester:
SENSOR CHECK (TEST MODE)
NOTICE:
When having replaced the master cylinder pressure, yaw
rate and deceleration sensors and/or the ECU, perform
zero point calibration of the master cylinder pressure, yaw
rate and deceleration sensors (See page DI±897).
HINT:
If the ignition switch is turned from the ON to the ACC or LOCK
position in test mode, test mode DTCs will be erased.
(a) Procedures for test mode:
(1) Turn the ignition switch OFF.
(2) Check that the shift lever is in the P position, and
turn the steering wheel to the neutral position.
(3) Using SST, connect terminals Ts and CG of the
DLC3.
SST 09843±18040
(4) Start the engine.
(5) Check that the ABS and VSC TRAC warning lights
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

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.

DI±922
± DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
111 6 Author: Date:
2005 SEQUOIA (RM1146U)
*1: As long as the following operations are not performed, the ABS warning light will not go OFF only by re-
pairing the trouble area.
(1) Drive the vehicle at 12 mph (20 km/h) for 30 seconds or more and check that the ABS warning light goes
off.
(2) Clear the DTC (See page DI±911).
HINT:
There is a possibility that the hand±held tester cannot be used when the ABS warning light is always ON.
DTC chart of VSC system:
DTC No.
(See Page)Detection ItemTrouble Area
C1201/51
(DI±936)Engine control system malfunction
Engine control system
C1202/52
(DI±937)Brake fluid level warning switch circuit

Brake fluid level

Brake fluid level warning switch

Brake fluid level warning switch circuit

Skid control ECU

CAN1 communication system

Translate ECU
C1203/53 *1
(DI±942)Malfunction in CAN1 communication

Skid control ECU

CAN1 communication system

ECM

Translate ECU
C1207/37
(DI±522)Reverse gear signal failureECT
C1223/43
(DI±945)Malfunction in ABS control systemABS control system
C1231/31
(DI±946)Malfunction in steering angle sensor

Steering angle sensor

Steering angle sensor communication circuit

Skid control ECU

Translate ECU

CAN communication system
C1232/32
(DI±951)Malfunction in deceleration sensor
Yaw rate (deceleration) sensor

Yaw rate (deceleration) sensor circuit
C1234/34
(DI±954)Malfunction in yaw rate sensor
Yaw rate (deceleration) sensor

Yaw rate (deceleration) sensor circuit
C1310/11
(DI±969)Open or short circuit in active brake booster solenoid circuit
Brake booster

Active brake booster solenoid circuit
C1311/12
(DI±971)Open or short circuit in brake inhibit relay circuit
Brake inhibit relay

Brake inhibit relay circuit
1335/35
(DI±946)Malfunction in steering angle sensor communication circuit

Steering angle sensor

Steering angle sensor communication circuit

Skid control ECU

Translate ECU

CAN1 communication system
C1340/47*2
(DI±977)Center diff. lock circuit malfunction

Center diff. lock position switch

Center diff. lock position switch circuit

Center diff. lock indicator light circuit

Translate ECU
C1360/61
(DI±983)Malfunction in master cylinder pressure sensor
Master cylinder pressure sensor

Master cylinder pressure sensor circuit

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