Lexus ES300 (2002 year). Service manual - part 83

BODY ELECTRICAL – ACCESSORIES

BE-61

CAUTION

The garage door or the gate could operate unintentionally while registering a transmitter code. There-
fore, make sure that there are no people near the garage door or the gate before carrying out this opera-
tion.

NOTE:

3. Transmitter Code Registration Procedure

The garage door opener contains an EEPROM in which the maximum of 3 types of transmitter recognition
codes can be registered. A transmitter code is registered into the EEPROM of the garage door opener accord-
ing to the following steps.

A:Press the button for registering transmitter codes continuously until the indicator light flashes slowly.

B: While keeping the garage door opener’s button pressed, place the transmitter for while you wish to register

the code within about 25 mm (1 in.) of the garage door opener and press the transmitter’s button.

C: After the flashing of the indicator light changes from slow to quick flashing, the registration of the trans-

mitter code has been completed. Then, release your fingers from the buttons of the garage door opener and
the transmitter.

D:To register the code of another transmitter, repeat the operation starting with step “A”. To register a new

code to the button that already has a code registered to it, select the button to which you wish to register
the new code and start the operation starting with step “A”.

 Before performing a transmitter code registration, stop the engine and pull the key from the igni-

tion key cylinder.

 The transmitter code of a garage door opener manufactured before 1982 cannot be registered in

this system.

For details of procedures of transmitter code registration, refer to the 2002 LEXUS ES300 Repair Manual
(Pub. No. RM911U) to register the codes correctly.

BODY ELECTRICAL – LIGHTING

BE-8

211BE52

151LBE67

Multi-reflector

Reflector 
(Multiple Parabolic Shape)

Headlight Bulb

Lens

Light Distribution

LIGHTING

HEADLIGHT

1. General

 The multi-reflector headlights have been adopted as standard equipment.
 HID (High Intensity Discharge) headlights that produce light with a longer reach and wider distribution

have been newly adopted as optional equipment for the low beams of all models in order to improve visibil-
ity.

2. Multi-Reflector Type Headlight

With the multi-reflector type headlights and taillights, the light from the bulbs is dispersed and distributed
through multiple parabolic shaped reflectors. As a result, the lens cut pattern is no longer provided in the cen-
ter of the lens, thus realizing a clear look.

 Light Distribution Imaginary Diagram 



BODY ELECTRICAL – LIGHTING

BE-9

151LBE15

Battery

Light Control
ECU

Xenon Gas

Light

Light

Metal Halide Bulb

Mercury Evaporation

Battery

CAUTION

The replacement of an HID (High Intensity Discharge) must be performed only by a LEXUS dealer.
Never touch the glass portion or the electrode portion of the bulb because high voltage that is generated
at those areas is very dangerous.

3. HID (High Intensity Discharge) Headlight System

General

The HID headlight system that has been newly adopted on the ’02 ES300 applies high voltage to the elec-
trodes on the light bulb to discharge arcs, causing the metal atoms that are enclosed in the bulb to emit light.

Construction and Operation

The HID headlight system consists of metal halide bulbs and a light control ECU. The basic operation and
construction are the same as in the ’02 LS430.

1) Metal Halide Bulb

a. Construction

The metal halide bulb contains xenon gas, mercury, and metal halide.

b. Operation

 When high voltage (approximately 20,000 volts) is applied to the electrodes of the metal halide bulb,

the xenon gas in the bulb emits light.

 As the temperature in the bulb rises, the mercury evaporates and causes arcs to be discharged.
 As the temperature in the bulb rises even further, the metal halide in the mercury arc separates into

metal atoms and iodine atoms.

 The separated metal atoms discharge light, which causes the bulb to emit light.

BODY ELECTRICAL – LIGHTING

BE-10

2) Light Control ECU

a. General

The light control ECU is an electronic control unit which is necessary for illuminating the metal halide
bulb. A light control ECU is located under each headlight unit. This ECU provides the functions Listed
below.

 Generates the high voltage (approximately 20,000 volts) which is applied to the electrodes of the

bulbs to enable the HID headlights to start to illuminate.

 Optimally controls the amperage and voltage in order to quickly provide an optimal amount of light

immediately after the bulbs have been turned ON and to enable the bulbs to continue to illuminate
in a stable manner.

 A fail-safe function is provided as a countermeasure against the high voltage that is generated in case

that a problem occurs in the headlight system.

b. Fail-Safe Function

The light control ECU executes the fail-safe actions listed below in accordance with the item that has
been detected.

Item

Outline

Detection of Abnormal
Input Voltage

If the voltage that is input to the light control ECU deviates from the
operating voltage (9-16 volts), the ECU stops illuminating the
headlights, and resumes illuminating the headlights once the voltage
reverts to the operating voltage range.
However, if the input voltage decreases after the headlights have
illuminated, the headlights will remain illuminated until the bulbs are
extinguished.

Detection of Abnormal
Output (Open Circuit
or Short Circuit) or
Flashing Bulb

If an abnormal condition (open or short circuit) occurs in the voltage that
is output by the light control ECU, or if the bulb flashes, the ECU stops
illuminating the headlights and will maintain this state until the power
is reinstated (by tuning the headlight control switch from OFF to ON).

Detection of Bulb Open

If a bulb is not inserted in its socket, the ECU stops generating high
voltage until the bulb is inserted correctly and the power is reinstated (by
turning the headlight control switch from OFF to ON or turning the
ignition switch from OFF to ON).