LR3/Disco 3
portion of the beam spread to enable the vehicle to be driven in opposite drive hand markets without applying blanking
decals to the headlamp lens. The beam is changed by removing the access cover at the rear of the lamp assembly and
moving a small lever located near the bulb holder, at the side of the projector module. Make sure that the headlamps are
off before removing the access cover.
The xenon bulbs illuminate when an arc of electrical current is established between two electrodes within the bulb. The
xenon gas sealed in the bulb reacts to the electrical excitation and the heat generated by the current flow. The xenon gas
reaction to the controlled current flow between the electrodes produces the blue/white light.
To operate at full efficiency, the xenon bulb goes through three stages of operation before full output for continuous
operation is achieved. The three phases are; start-up phase, warm-up phase and continuous phase.
In the start-up phase, the bulb requires an initial high voltage starting pulse of 18000 to 28000 volts to establish the arc.
This is produced by the igniters. The warm-up phase begins once the arc is established. The xenon control modules
regulate the supply to the bulbs to 2.6A which gives a lamp output of 75W. During this phase, the xenon gas begins to
illuminate brightly and the environment within the bulb stabilises ensuring a continual current flow between the electrodes.
When the warm-up phase is complete, the xenon control modules change to continuous phase. The supply voltage to the
bulb is reduced and the operating power required for continual operation is reduced to 35W.
The xenon system is controlled by the CJB, the two xenon control modules and the two igniters. The xenon control
modules (one per headlamp) receive an operating voltage from the CJB when the headlamps are switched on. The
modules regulate the power supply required through the phases of start-up.
The igniters (one per headlamp) generate the initial high voltage required to establish the arc. The igniters have integral
coils which generate high voltage pulses required for start-up. Once the xenon bulbs are operating, the igniters provide a
closed circuit for regulated power supply from the control modules.
Turn Signal Lamp
The turn signal lamp is incorporated into the outer part of the headlamp assembly. The lamp is located above the side
lamp/cornering lamp. The turn signal lamp uses an 27W/7W S8W wedge bulb. The bulb is fitted into a holder which is
connected via wires to the main connector on the headlamp housing. The holder is fitted into an aperture in the headlamp
housing and rotated to lock into position. The bulb is accessible via a sealed cover which is attached to the rear of the
headlamp housing. The cover is secured in the housing by rotating in a clockwise direction until locked. Access to the
cover requires removal of the headlamp from the front carrier assembly and removal of the outer locking plate from the
headlamp.
The turn signal lamps are operated by the left hand steering column multifunction switch or by the hazard flasher switch.
The steering column multifunction switch is only active with the ignition switch in the ignition position (II), the hazard
flasher switch is active at all times. When active, the turn signal lamps will flash at a frequency cycle of 380ms on and
380ms off.
If a bulb fails, the remaining turn signal lamps bulbs continue to flash at normal speed. The turn signal indicators in the
instrument cluster will flash at double speed to indicate the bulb failure to the driver.
Side Lamp
The side lamp is incorporated into the outer part of the headlamp assembly and is located below the turn signal indicator
lamp. The side lamp shares the same housing and reflector as the cornering lamp and static bending lamp (when fitted).
The side lamp uses a capless W5W wedge fitting bulb which locates into a holder which is connected via wires to the
main connector on the headlamp housing. The holder is a push fit into a receptacle in the headlamp housing. The bulb is
accessible via a removable cover at the rear of the headlamp housing. Access to the cover requires removal of the
headlamp from the front carrier assembly and partial removal of the outer locking plate from the headlamp.
The side lamps are operated by selecting side lamps or headlamps on the lighting control switch. The side lamps are
operational at all times and are not dependant on the ignition switch position. The side lamps will also be illuminated when
the lighting control switch is in the AUTO position and a 'lights on' signal is received by the CJB from the rain/light sensor.
Cornering Lamp
NOTE :
The cornering lamps are not fitted to NAS market vehicles
