Toyota Sequoia (2005). Manual - part 231

F16807

GND

F19430

GND

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–719

913

RM+ (S25–20) – 

GND (S25–22)

R–L – W–B

Height Control

Compressor

Motor Lock (+)

Engine idling, vehicle height changes from ”NORMAL” to

”HIGH” by pressing the height control switch (While

height control compressor assy is working).

Below 1.0 V

RM– (S25–21) – 

Body ground

BR–Y – W–B

Height Control

Compressor

Motor Lock (–)

Always

Below 1.0 V

GND (S25–22) – 

Body ground

W–B – 

Body ground

Ground

Always

Below 1.0 V

B (S25–24) – 

GND (S25–22)

V – W–B

Battery

IG switch ON

10 to 14 V

LO (S25–26) – 

P

W B

Height Control

I di

t

”LO”

Engine idling, vehicle height is ”NORMAL” 

→

P

i

th ”DOWN” b tt

f th h i ht

t l

it h

10 V or more 

→

LO (S25 26)   

GND (S25–22)

P – W–B

Indicator ”LO”

Signal

Pressing the ”DOWN” button of the height control switch

turns on the ”LO” indicator lamp (*1)

10 V or more 

→

Below 5 V

STP (S25–27) – 

G Y

W B

Stop Light

B k

d l d

d

R l

d

10 to 14 V 

→

STP (S25 27)   

GND (S25–22)

G–Y – W–B

Sto  Light

Switch

Brake pedal depressed 

→

 Released

10 to 14 V 

→

Below 1.5 V

SIL (S25–30) – 

GND (S25–22)

G–R – W–B

Diagnosis Sig-

nal

Hand–held tester is connected to DLC3

Pulse generation

(See waveform 3)

DOOR (S25–31) – 

R

W B

D

Si

l

IG switch ON, each door opened 

→

Below 1.5 V

DOOR (S25 31)   

GND (S25–22)

R – W–B

Door Signal

IG 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

”DOWN” Signal

IG switch ON, ”DOWN” button of height control switch

pushed in 

→

”DOWN” button of height control switch released

Below 1.5 V 

→

10 to 14 V

BAT (S25–25) – 

GND (S25–22)

V – W–B

Battery

Always

10 to 14 V

CANL (S25–28) – 

GND (S25–22)

W – W–B

CAN Commu-

nication Signal

IG switch ON

Pulse generation

(See waveform 1)

CANH (S25–29) – 

GND (S25–22)

G – W–B

CAN Commu-

nication Signal

IG switch ON

Pulse 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):

Item

Contents

Terminal

CANL – GND

Tool setting

1V/DIV, 10

µ

s/DIV

Vehicle condition

Ignition SW ON, Engine stopped

Waveform 2 (Reference):

Item

Contents

Terminal

CANH – GND

Tool setting

1V/DIV, 10

µ

s/DIV

Vehicle condition

Ignition SW ON, Engine stopped

F19431

GND

DI–720

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

914

Waveform 3 (Reference):

Item

Contents

Terminal

SIL – GND

Tool setting

5V/DIV, 1ms/DIV

Vehicle condition

Communicating using hand–held tester

DIDD7–01

C00083

DLC3

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–721

915

DIAGNOSIS SYSTEM

1.

DIAGNOSIS SYSTEM

(a)

Inspect the battery voltage.
Battery voltage: 11 to 14 V

If voltage is below 11 V, recharge the battery before proceeding.
(b)

Check DLC3.
The suspension control ECU uses the CAN system and
ISO 9141–2 for communication. The terminal arrange-
ment of the DLC3 complies with SAE J1962 and matches
the ISO 9141–2 format.
Verify the conditions listed in the table below:

Symbols (Terminal No.)

Terminal Description

Condition

Specified Condition

SIL(7) – SG(5)

Bus ”+” line

During communication

Pulse generation

CG(4) – Body ground

Chassis ground

Always

Below 1 

Ω

SG(5) – Body ground

Signal ground

Always

Below 1 

Ω

BAT(16) – Body ground

Battery positive

Always

11 to 14 V

CANH(6) – CANL (14)

HIGH–level CAN bus line

IG switch OFF

54 to 67 

Ω

CANH(6) – Battery positive

HIGH–level CAN bus line

IG switch OFF

1 M

Ω

 or higher

CANH(6) – CG(4)

HIGH–level CAN bus line

IG switch OFF

3 K

Ω

 or higher

CANL(14) – Battery positive

LOW–level CAN bus line

IG switch OFF

1 M

Ω

 or higher

CANL(14) – CG(4)

LOW–level CAN bus line

IG switch OFF

3 K

Ω

 or higher

HINT:
If the hand–held tester display shows UNABLE TO CONNECT
TO VEHICLE when the cable of the hand–held tester is con-
nected to the DLC3, the ignition switch is turned ON and the tes-
ter is operated, there is a problem on the vehicle side or tester
side.

If communication is normal when the tester is connected
to another vehicle, inspect the DLC3 on the original ve-
hicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tester itself, so consult the service department listed in the
tester’s instruction manual.

(c)

DTCs (Normal mode)
(1)

DTCs are memorized in the suspension control
ECU and read by using the SST check wire or the
hand–held tester (see page 

DI–723

 for the proce-

dure of DTCs check).

SST

09843–18040

(d)

Test mode (Input signal check)
(1)

By switching from normal mode into test mode, you
can inspect the height control switch, height control
mode select switch, door courtesy lamp switch, and
stop lamp switch (see page 

DI–711

).

F16799

DI–722

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

916

(e)

Check the indicator lamp.
(1)

Turn the ignition switch to the ON position.

(2)

Check that the height control manual indicator lamp
and the height control indicator lamp come on for 2
seconds.

If the indicator check result is not normal, proceed to trouble-
shooting for the height control indicator lamp circuit (See page

DI–785

) and the height control manual indicator lamp circuit

(See page 

DI–789

).