Toyota Sequoia (2005). Manual - part 489

–

DIAGNOSTICS

BODY CONTROL SYSTEM

DI–1751

1945

INSPECTION PROCEDURE

HINT:
When using the hand–held tester, start the inspection from step 1 and when not using the hand–held tester,
start from step 2.

1

Check headlight control switch using hand–held tester.

PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

Turn the ignition switch ON.

CHECK:
According to the display on the tester, read the ”DATA LIST”.
BODY ECU:

Item

Measurement Item/Display

(Range)

Normal Condition

Diagnostic Note

AUTO LIGHT SW

Light control switch (AUTO)/ON or

OFF

ON: Light control switch position is

AUTO

OFF: Light control switch position

is not AUTO

–

HEAD LIGHT SW

Light control switch (HEAD)/ON or

OFF

ON: Light control switch position is

HEAD

OFF: Light control switch position

is not HEAD

–

TAIL LIGHT SW

Light control switch (TAIL)/ON or

OFF

ON: Light control switch position is

TAIL

OFF: Light control switch position

is not TAIL

–

OK:

The indication on the tester switches between ON and OFF in accordance with the light control
switch status.

OK

Proceed to next circuit inspection shown in
problem symptoms table (See page 

DI–1686

).

NG

2

Check light control switch (See page 

BE–27

).

NG

Replace light control switch.

OK

DI–1752

–

DIAGNOSTICS

BODY CONTROL SYSTEM

1946

3

Check wire harness and connector between light control switch and body ECU,
light control switch and body ground (See page 

IN–35

).

NG

Repair or replace wire harness or connector.

OK

Proceed to next circuit inspection shown in
problem symptoms table
(See page 

DI–1686

).

I03114

A27
Automatic Light
Control Sensor

CLTS

Y

R–G

BR

CLTB

CLTE

Body ECU

12

B6

4

1

3

4

B6

3

B6

CLTS

CLTB

CLTE

–

DIAGNOSTICS

BODY CONTROL SYSTEM

DI–1753

1947

Automatic light control sensor circuit

CIRCUIT DESCRIPTION

The body ECU detects the ambient light level outside the vehicle via the automatic light control sensor.
The body ECU turns the headlights ON and OFF based on the ambient light level sensed by the automatic
light control sensor.

WIRING DIAGRAM

DI1OL–28

DI–1754

–

DIAGNOSTICS

BODY CONTROL SYSTEM

1948

INSPECTION PROCEDURE

1

Check automatic light control sensor.

When using hand–held tester:
PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

Turn the ignition switch and hand–held tester main switch ON.

BODY ECU:

Item

Measurement Item/Display

(Range)

Normal Condition

Diagnostic Note

ILLUMINATE RATE

Illumination rate information/

MIN: 0 MAX: 99.99

Condition value will be displayed

Normal value: 0.8 ms to 22.0 ms

–

CHECK:
The illumination rate value should change within the following range such as when the light sensor is ex-
posed to light or covered by hand.
OK:

0.8 ms to 22.0 ms

HINT:
Time needed for the light sensor to generate one cycle of frequency according to the brightness.
When not using hand–held tester (See page 

BE–27

):

NG

Replace automatic light control sensor.

OK

2

Check harness and connector between automatic light control sensor and body
ECU (See page 

IN–35

).

NG

Repair or replace wire harness or connector.

OK

Proceed to next inspection shown in problem
symptoms table (See page 

DI–1686

).