Toyota Sequoia (2005). Manual - part 243

F19446

W

4

1

G–Y

1

4A

11

4A

G–Y

27

S25 STP

Battery

B

ALT

8

5

W

1

1L

STOP

2

1F

S14
Stop Light Switch

Sub J/B No. 4

Suspension Control
ECU

Instrument Panel J/B

F10
Fusible Link Block

1L

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–767

961

DTC

C1782/82 Stop Light Switch Circuit (Test Diagnosis)

CIRCUIT DESCRIPTION

When the brake pedal is depressed, the stop light comes on and the signal is input to the STP terminal of
the suspension control ECU.
HINT:
This DTC is output only when the sensor signal check is done.

DTC No.

DTC Detecting Condition

Trouble Area

C1782/82

The signal from the stop light switch assy does not change.

Stop light switch assy

Stop light switch circuit

Suspension control ECU

WIRING DIAGRAM

DIDE7–01

F16805

Wire Harness View:

S25

STP

DI–768

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

962

INSPECTION PROCEDURE

1

Inspect stop light.

CHECK:
Check that the stop light comes on when the brake pedal is depressed and goes off when the brake pedal
is released.
OK:

Stop light operates normally.

NG

Go to step 3.

OK

2

Inspect suspension control ECU.

PREPARATION:
Disconnect the ECU connector.
CHECK:
Measure the voltage between terminal S25–27 (STP) of the
suspension control ECU and body ground when the stop light
switch is ON and OFF.
OK:

Switch condition

Specified condition

Brake pedal depressed (ON)

10 to 14 V

Brake pedal released (OFF)

Below 1 V

NG

Repair or replace harness connector.

OK

Replace suspension control ECU
(See page 

IN–35

).

I21525

Free

Pushed in

F16805

Wire Harness View:

S25

STP

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

DI–769

963

3

Inspect stop light switch assy.

PREPARATION:
Disconnect the stop light switch assy connector.
CHECK:
Check resistance between terminals 1 and 4 of the stop light
switch assy.
OK:

Switch condition

Tester connection

Specified condition

Switch pin free

1 – 4

Below 1 

Ω

Switch pin pushed in

1 – 4

10 k

Ω

 or higher

NG

Replace stop light switch assy.

OK

4

Inspect suspension control ECU.

PREPARATION:
Disconnect the ECU connector.
CHECK:
Measure the voltage between terminal S25–27 (STP) of the
suspension control ECU and body ground when the stop lamp
switch is ON and OFF.
OK:

Switch condition

Specified condition

Brake pedal depressed (ON)

10 to 14 V

Brake pedal released (OFF)

Below 1 V

NG

Repair or replace harness connector.

OK

Replace suspension control ECU
(See page 

IN–35

).

F19447

Body ECU

Suspension Control
ECU

ACTY

20

B6

31

S25 DOOR

R

DI–770

–

DIAGNOSTICS

AIR SUSPENSION SYSTEM

964

DTC

C1783/83 Door Courtesy Switch Circuit 

(Test Diagnosis)

CIRCUIT DESCRIPTION

The door courtesy light switch turns on when the door is opened and turns off when the door is closed.
The signal is sent from the body ECU and the back door ECU into the DOOR terminal of the suspension
control ECU when any door is open.
HINT:
This DTC is output only when the sensor signal check is done.
For courtesy light switch connection, see the system diagram on page 

DI–698

.

DTC No.

DTC Detecting Condition

Trouble Area

C1783/83

Door courtesy light switch signal does not change.

Door courtesy light switch

Back door lock assy (Back door courtesy light switch)

Door courtesy light switch circuit

Body ECU

Back door ECU

Suspension control ECU

WIRING DIAGRAM

DIDEA–01