Toyota Sequoia (2005). Manual - part 244

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DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–771

965

INSPECTION PROCEDURE

1

Inspect courtesy light switch.

CHECK:
Check that the open door warning light comes on when any door or back door is opened and goes off when
all the doors are closed.
OK:

Courtesy light operates normally.

NG

Check open door warning light
(See page 

DI–1608

).

OK

F16805

Suspension Control ECU:

DOOR

S25

I27700

Body ECU:

ACTY

B6

DI–772

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DIAGNOSTICS

AIR SUSPENSION SYSTEM

966

2

Check harness and connector (Suspension control ECU – Body ECU).

PREPARATION:
Disconnect the body ECU and suspension control ECU con-
nectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester connection

(Symbol)

Condition

Specified condition

B6–20 (ACTY) – 

S25–31 (DOOR)

Always

Below 1 

Ω

B6–20 (ACTY) – 

Body ground

Always

10 k

Ω

 or higher

NG

Repair or replace harness or connector.

OK

I27702

Body ECU Wire Harness View:

B6

ACTY

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DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–773

967

3

Inspect body ECU (ACTY output).

PREPARATION:
Reconnect the body ECU and suspension control ECU connec-
tors.
CHECK:
Measure the voltage between terminal B6–20 (ACTY) of the
multiplex network body ECU and body ground when doors are
opened and closed.
OK:

Door condition

Specified condition

Each door opened

Below 1.5 V

All doors closed

10 to 14 V

NG

Replace body ECU (See page 

IN–35

).

OK

Replace suspension control ECU
(See page 

IN–35

).

F19448

H12
Height Control Switch

Suspension Control
ECU

IM

S25

3

13

S25

HI

LO

HSW

LWS

DNSW

32

4

2

W–B

UPSW

W

L–B

E

DI–774

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DIAGNOSTICS

AIR SUSPENSION SYSTEM

968

DTC

C1786/86 Height Control Switch Circuit 

(Test Diagnosis)

CIRCUIT DESCRIPTION

Vehicle height can be chosen by pressing the height control switch.
By pressing the ”UP” side, vehicle height goes up.
By pressing the ”DOWN” side, vehicle height goes down.
HINT:
This DTC is output only when the sensor signal check is done.

DTC No.

DTC Detecting Condition

Trouble Area

C1786/86

Height control switch signal does not change.

Height control switch

Height control switch circuit

Suspension control ECU

WIRING DIAGRAM

DIDED–01