Lexus LS400 (2000 year). Service manual - part 54

Z14880

Connector B

Connector A

I03491

I03492

BE–44

–

BODY ELECTRICAL

HEADLIGHT AND TAILLIGHT SYSTEM

1907

15.

INSPECT DAYTIME RUNNING LIGHT RELAY NO.3
AND NO.4 CONTINUITY

Tester connection

Condition

Specified condition

A1 – B3

Constant

Continuity

A3 – A5

Constant

Continuity

B3 – B4

Constant

Continuity

A2 – A5

Apply battery positive voltage between

terminal A1 and B3.

Continuity

B1 – B2

Apply battery positive voltage between

terminal B3 and B4.

Continuity

If continuity is not as specified, replace the relay.

16.

INSPECT AUTOMATIC LIGHT CONTROL
AUTO ON:

(a)

Turn the ignition switch ON.

(b)

Turn the light control switch to AUTO.

(c)

Gradually cover the top of the sensor.

(d)

Verify that the lights should turn ON the accessory lights
and the headlights.

17.

INSPECT AUTOMATIC LIGHT CONTROL
AUTO OFF:

(a)

Gradually expose the sensor.

(b)

Verify that the lights should turn OFF the headlights and
the accessory lights.

Z14888

1 2 3 4 5 6 7 8

Wire Harness Side

–

BODY ELECTRICAL

HEADLIGHT AND TAILLIGHT SYSTEM

BE–45

1908

18.

INSPECT LIGHT–OFF CONDITION

(a)

Turn the ignition switch ON.

(b)

Gradually cover the top of the sensor.
Lights auto ON:

(c)

Verify that the lights will go out when light control switch
position OFF or the area surrounding the sensor gets
bright or open the driver’s door while the ignition switch is
OFF.

19.

INSPECT LIGHTS–ON CONDITION

(a)

Open the driver’s door while the ignition switch is OFF.

(b)

Turn the light control switch to AUTO leaving the door
open and cover the top of the sensor, and verify that the
lights go on when the ignition switch is turned ON.

20.

ADJUST AUTOMATIC LIGHT CONTROL SENSOR

Using the LEXUS hand–held tester with customize soft
installed, adjust the automatic light control sensor.

If response is too quick, turn the knob counterclock-
wise.

If response is too slow, turn the knob clockwise.

21.

INSPECT AUTOMATIC LIGHT CONTROL SENSOR
CIRCUIT
Connector disconnected

Disconnect the connector from the sensor and inspect the con-
nector on the wire harness side, as shown in the chart.

Tester connection

Condition

Specified condition

6 – Ground

Constant

Continuity

4 – Ground

Ignition switch position LOCK or ACC

No voltage

4 – Ground

Ignition switch position ON

5.2 – 9.0 V

5 – Ground

Ignition switch position LOCK or ACC

No voltage

5 – Ground

Ignition switch position ON

Battery positive voltage

If circuit is as specified, perform the inspection on the following
page.
If the circuit is not as specified, inspect the circuit connected to
other parts.

N12999

From Back Side

6 5

4

BE–46

–

BODY ELECTRICAL

HEADLIGHT AND TAILLIGHT SYSTEM

1909

Connector connected
Connect the wire harness side connector to the sensor and in-
spect wire harness side connector from the back side, as
shown.
HINT:

Ignition switch ON.

Light control switch AUTO.

Vehicle’s surroundings are bright.

Tester connection

Condition

Specified condition

6 – Ground

Constant

1 V or less

5 – Ground

Ignition switch position LOCK or ACC

1 V or less

5 – Ground

Ignition switch position ON

9.5 V or more

4 – Ground

Vehicle’s surroundings are dark.

(Sensor is covered)

Taillight and headlight are ON

If circuit is as specified, try replacing the sensor with a new one.
If the circuit is not as specified, inspect the circuit connected to
other parts.

BE11V–01

I09287

Adjusting Bolt A

Low Beam Center Mark

High Beam Center Mark

VOR Mark

Halogen Type:

I03416

Low Beam Center Mark

H

9.84 ft

W

V (RH)

V (LH)

V

V

V (LH)

V (RH)

W

0.4

°

0.4

°

45

°

15

°

2.7
in.

–

BODY ELECTRICAL

HEADLIGHT AND TAILLIGHT SYSTEM

BE–47

1910

ADJUSTMENT

1.

Halogen Type:
ADJUST HEADLIGHT AIM ONLY

(a)

Put the vehicle in below conditions.

Make sure the body around the headlight is not de-
formed.

Park the vehicle on a level spot.

The driver gets into the driver’s seat and puts the
vehicle in a state ready for driving (with a full tank).

Bounce the vehicle several times.

(b)

Prepare the thick white colored paper.

(c)

Stand the paper perpendicularly and ensure the distance
from it to the head lights is 9.84 ft.

(d)

Ensure that the center line of vehicle and the paper are
at a 90 degree angle as shown in the illustration.

(e)

Draw a horizontal line on the paper where the head lights
(low beam center mark) of the vehicle are to be.

(f)

Draw a vertical line on the paper where the center line of
the vehicle is to be. (V line)

(g)

Turn the head lights ON.

(h)

Check that the head lights light up the paper as shown in
the illustration.

HINT:
As shown in the illustration, adjust aiming of the LH and RH
lights respectively.