Part 1
Exterior Lighting
COMPONENT LOCATION
Exterior Lighting Part 1:
Exterior Lighting Part 2:
INTRODUCTION
The lighting systems are controlled by the Auxiliary Junction Box (AJB) and the CJB (central junction box). The two boxes contain fuses, relays and microprocessors to control the power supply and functionality of the lighting systems.
Driver lighting selections using the LH (left-hand) steering column multifunction switch or the auxiliary lighting switch are passed to the CJB (central junction box) via the instrument cluster.
The lighting system has an 'auto' lights function which is controlled by the CJB (central junction box) on receipt of signals from the light sensor. The exterior lights are turned on or off in response to ambient light signals from the light sensor via the instrument cluster.
Two levels of headlamp are available; Bi-xenon or Bi-xenon with Adaptive Front lighting System (AFS). The AFS headlamp has a swiveling projector module which moves the headlamp beam in the direction of travel. The AFS headlamp also features a cornering/static bending lamp which illuminates the area at the side of the vehicle when turning into driveways for example.
The tail lamp is in two parts. The turn signal indicator, side and stop lamps are located in each rear fender. The reverse and rear fog lamps are located in separate units attached to the liftgate. The locations of the fog and reverse lamps changes depending if the vehicle is LHD (left-hand drive) or RHD (right-hand drive). The turn signal indicator, side and stop lamps use conventional glass filament bulbs. The rear fog and reverse lamp use colored LED (light emitting diode).
EXTERIOR BULB TYPE/RATING
The following table shows the bulbs used for the exterior lighting system and their type and specification.
CENTRAL JUNCTION BOX AND AUXILIARY JUNCTION BOX
The CJB (central junction box) is an integrated unit located in the passenger compartment LH (left-hand) side on the 'A' pillar.
The Auxiliary Junction Box (AJB) is located in a central position, behind the rear seat.
CJB (central junction box) Control
The CJB (central junction box) receives inputs from the following switches via the instrument cluster and the medium speed CAN (controller area network) bus:
- LH (left-hand) steering column multifunction switch Side lamp position Headlamp position Automatic (AUTO) position Timer delay positions Turn signal indicators Headlamp flash and high beam
- Side lamp position
- Headlamp position
- Automatic (AUTO) position
- Timer delay positions
- Turn signal indicators
- Headlamp flash and high beam
- Stop lamp switch
- Hazard flasher switch
- Sunload/Light sensor.
The following lamps are controlled by the CJB (central junction box) :
- Front side lamps
- Front side marker lamps
- Headlamps
- Cornering lamps
- Front fog lamps.
AJB Control
The following lamps are controlled by the AJB:
- Rear fog lamp
- Reverse lamp
- Stop lamps
- High mounted stop lamp
- Rear side lamps
- Rear side marker lamps
- Licence plate lamps
- Front and rear turn signal indicators and side repeaters
The AJB is also connected via a hardwired connection to the hazard flasher switch.
Circuit Protection
The AJB and the CJB (central junction box) provide circuit protection for all exterior lighting circuits. The exterior lighting circuits are protected by Field Effect Transistors (FETs). Operation of the exterior lighting circuits is protected by the FETs which can detect overloads and short circuits. The FETs respond to heat generated by increased current flow caused by a short circuit.
On a normal circuit this would cause the fuse to blow. The FETs respond to the heat increase and disconnect the power supply to the affected circuit. When the fault is rectified or the FET has cooled, the FET will reset and operate the circuit normally. If the fault persists the FET will cycle, disconnecting and reconnecting the power supply.
The CJB (central junction box) and the AJB store fault codes which can be retrieved using a Jaguar approved diagnostic system. The fault code will identify that there is a fault on a particular output which will assist with fault detection.
Alarm Indications
The exterior lighting system is used for alarm arm and disarm requests.
When the driver locks and arms the vehicle, a visual indication of a successful lock and arm request is displayed to the driver by a single flash of the hazard flashers. If the vehicle is superlocked then the hazard flashers will flash a second time (200 ms off and 200 ms on) to confirm the superlock request.
When the driver unlocks the vehicle, a visual indication of a successful lock and disarm request is displayed to the driver by the hazard flashers operating twice (200 ms off and 200 ms on).
If the alarm is triggered, the hazard flashers are operated for ten 30 seconds cycles of 200 ms on and 200 ms off with a 10 seconds delay between each cycle.
NOTE: On NAS vehicles the delay between cycle when the alarm is triggered is 60 seconds. The alarm triggered hazard flasher operation varies depending on market.
Lights on Warning Chime
When the ignition is in the off mode or accessory mode conditions and the lighting switch is in the side lamp or headlamp position, a warning chime will sound if the driver's door is opened. This indicates to the driver that the exterior lights have been left switched on.
The chime is generated from the instrument cluster sounder on receipt of a lights on signal, a driver's door open signal and an ignition off or accessory mode signal via a medium speed CAN (controller area network) bus signal from the CJB (central junction box).
Crash Signal Activation
When a crash signal is transmitted from the restraints control module, the AJB activates the hazard flashers. The hazard flashers continue to operate until the ignition is in the off or accessory modes and then returned to the ignition on mode. Once this condition has occurred, the restraints control module will cease transmission of the crash signal.
Headlamp Timer
The AJB controls a headlamp timer function which allows the headlamps to remain on for a period of time after leaving the vehicle. This is a driver convenience feature which illuminates the driveway after leaving the vehicle.
To select this feature, the lighting control switch on the steering column multifunction switch must be in one of the three headlamp timer positions when the ignition mode is changed from ignition on mode to off mode. The timer function will then be initiated and the low beam headlamps will be illuminated for the selected timer period.
NOTE: If the lighting switch is in the AUTO position, the headlamp timer will not function when the ignition mode is changed to off.
The timer period can be adjusted using one of the 3 positions on the lighting control switch on the LH (left-hand) steering column multifunction switch. The 3 switch positions correspond to timer values of 30, 60 and 120 seconds.
LIGHTING CONTROL SWITCH
The lighting control switch is located on the LH (left-hand) steering column multifunction switch. The switch is a rotary control with positions for the following lighting selections:
- Off
- Side lamps
- Headlamps
- AUTO headlamps
- Headlamp timer (3 time period selections).
The steering column multifunction switch also provides for the selection of low and high beam headlamps and also the headlamp flash function.
The steering column multifunction switch is connected to the instrument cluster by 3 wires. Two wires supply a signal voltage to the lighting switch and the headlamp timer positions. The third wire is a common ground. Each switch position is connected to the ground return via resistors which vary the return voltage to the instrument cluster. The instrument cluster senses the voltage returning and determines the switch position selected. The instrument cluster then generates an applicable message which is sent to the AJB and the CJB (central junction box) on the medium speed CAN bus for activation of the selected exterior lamps.
The steering column multifunction switch also provides the control for the turn signal indicators. The switch can be pushed down to select the LH (left-hand) turn signal indicators or pushed up to select the RH (right-hand) turn signal indicators. The switch has 2 positions. If the switch is pushed up or down gently and held, the turn signal indicators will operate until the switch is released, if the switch is pushed past a detent, the switch can be released and the selected position will automatically be cancelled when the manoeuvre is completed. If a turn signal indicator bulb fails, the green turn signal indicator warning indicator in the instrument cluster will flash at twice the normal rate and the audible ticking will also be at twice the normal rate.
The steering column multifunction switch also has a lane change function which is configurable by the dealer. If the switch is gently pushed to either turn signal indicator direction and then released, the turn signal indicators will flash 3 times and then automatically cancel.
AUXILIARY LIGHTING SWITCH
The auxiliary lighting switch is located in the instrument panel, adjacent to the steering column. The switch has 2 buttons which select the front an rear fog lamps. The buttons are non-latching momentary switches.
The auxiliary lighting switch is connected to the instrument cluster by 3 wires. Two wires supply a signal voltage to the each fog lamp switch. The third wire is a common ground. Each switch position is connected to the ground return via a series of resistors which vary the supply voltage from the instrument cluster. The instrument cluster senses the voltage and determines the switch position selected. The instrument cluster then generates an applicable message which is sent to the AJB and the CJB (central junction box) on the medium speed CAN bus for activation of the selected fog lamps.
The front fog lamps can only be activated when the ignition is in the ignition power mode and side lamps or headlamps are active. The rear fog lamps can only be activated if the low beam headlamps are on or if the side lamps and front fog lamps are on. A second press of each fog lamp button will switch of the selected fog lamps. If the lighting control switch or the ignition is changed to the off mode, then both fog lamps will be switched off and will need to be re-selected if required.
HEADLAMP ASSEMBLY
Two types of headlamp are available; Bi-Xenon and Adaptive Front lighting System (AFS). The headlamps are located with a locating dowel through the upper front bumper bracket and secured with 3 bolts to the front body structure. Bulb replacement requires the removal of the complete headlamp assembly.
The rear of the headlamp unit has removable access panels which allow access to the bulbs for replacement. A large cover, which is rotated anti-clockwise to remove allows access to the xenon D1S bulb. Another removable cover provides access to the corning lamp bulb and the side lamp bulb, which is retained with a spring clip. A smaller cover can be rotated anti-clockwise to provide access to the turn signal indicator bulb and the side marker lamp bulb.
The headlamps have two adjustment screws on the rear which allow for the manual setting of the vertical and horizontal alignment.
On NAS vehicles the headlamp is regarded as 'Visual Optically Left' aiming. The adjustment screws have to turned equal amounts to maintain the correlation in the vertical axis only. There is no horizontal adjustment.
Each headlamp has an integral 16 pin connector which provides inputs and outputs for the various functions of the headlamp assembly.
The low beam headlamps are switched on when the ignition is in the ignition mode and:
- the lighting control switch is in the headlamp position
- the lighting control switch is in the AUTO position and a 'lights on' signal is received by the CJB (central junction box) from a 'lights on' message generated by the AJB.
The low beam headlamps can also be operated by the headlamp timer function.
The high beam headlamps are switched on when the ignition is in the ignition mode and:
- The low beam headlamps are selected on or activated via the AUTO feature and the LH (left-hand) steering column multifunction switch is pushed forward, away from the driver
The high beam lamps will be switched off when:
- The LH (left-hand) steering column multifunction switch is moved rearwards, towards the driver.
- The low beam headlamps are switched off
- The ignition mode is changed to accessory or off mode.
WARNING: The Xenon system generates up to 28000 volts and contact with this voltage could lead to fatality. Make sure that the headlamps are switched off before working on the system.
The following safety precautions must be followed when working on the xenon headlamp system:
- DO NOT attempt any procedures on the xenon headlamps when the lights are switched on.
- Handling of the D1S xenon bulb must be performed using suitable protective equipment, for example gloves and goggles. The glass part of the bulb must not be touched.
- Xenon bulbs must be disposed of as hazardous waste.
- Only operate the lamp in a mounted condition in the reflector.
The xenon headlamp is known as Bi-Xenon because it operates as both a low and high beam unit. The xenon lamp or High Intensity Discharge (HID) lamp as they are sometime called, comprises an ellipsoidal lens with a solenoid controlled shutter to change the beam output from low to high beam.
NOTE: If the lighting control switch is in the OFF position, the xenon lamps operate when the high beam 'flash' function is operated.
The xenon headlamp system is controlled by the CJB (central junction box) using a control module for each headlamp and an igniter. The control modules and the igniters provide the regulated power supply required to illuminate the xenon bulbs through their start-up phases of operation.
Xenon Headlamp Construction
Xenon Bulb Replacement
The xenon headlamp is a self contained unit located within the headlamp assembly. The unit comprises a reflector, an adaptor ring, the lens, a shutter controller and the xenon bulb, which together is an assembly known as the projector module.
The reflector is curved and provides the mounting for the xenon bulb. The bulb locates in a keyway to ensure correct alignment in the reflector and is secured by a plastic mounting ring. The bulb is an integral part of the igniter and is electrically connected by a connector located in the igniter unit.
The shutter controller is a solenoid which operates the shutter mechanism via a lever. The shutter is used to change the beam projection from low beam to high beam and visa versa.
The xenon bulbs illuminate when an arc of electrical current is established between 2 electrodes within the bulb. The xenon gas sealed in the bulb reacts to the electrical excitation and the heat generated by the current flow to produce the characteristic blue/white light.
To operate at full efficiency, the xenon bulb goes through 3 full stages of operation before full output for continuous operation is achieved. The 3 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 up to 30000 volts to establish the arc. This is produced by the igniter. The warm-up phase begins once the arc is established. The xenon control module regulates the supply to the bulb 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 stabilizes, ensuring a continual current flow between the electrodes. When the warm-up phase is complete, the xenon control module changes to continuous phase. The supply voltage to the bulb is reduced and the operating power required for continual operation is reduced to 35W. The process from start-up to continuous phase is completed in a very short time.
The xenon control modules (one per headlamp) receive an operating voltage from the CJB (central junction box) 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 the regulated power supply from the control modules.
Turn Signal Indicator Lamp
The turn signal indicator lamp is incorporated into the outer part of the headlamp assembly, outboard of the projector module. The turn signal indicator lamp uses a PY21W bayonet orange colored bulb in Rest Of World (ROW) markets. A S8W 27/7W wedge bulb is used in NAS markets.
The bulb is fitted into a holder which connects with contacts in the headlamp housing. The holder is fitted into an aperture in the headlamp housing and is rotated to lock in position. Access to the turn signal indicator bulb requires removal of the headlamp assembly.
The turn signal indicator lamps are operated by the LH (left-hand) steering column multifunction switch or by the hazard flasher switch. The steering column multifunction switch is only active when the ignition is the ignition mode. The hazard flasher switch is active at all times. When active, the turn signal indicator lamps flash at a frequency cycle of 400 ms on and 400 ms off.
If a bulb fails, the remaining turn signal indicator lamps continue to flash at the normal speed. The applicable turn signal indicator in the instrument cluster will flash at double speed to indicate the failure to the driver.
Side Lamp
The side lamp is incorporated into the outer part of the headlamp assembly, above the cornering lamp. The side lamp shares the same housing and reflector as the cornering lamp.
The side lamp uses a W5W wedge fitting, orange colored bulb which is fitted in a holder and connected by wires to the main headlamp connector. The holder is a push fit into a receptacle in the headlamp housing. The bulb is accessible by removal of the cover on the side of the headlamp. Access to the bulb and the cover requires removal of the headlamp assembly.
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 mode. 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 (central junction box) from a 'lights on' message generated by the AJB.
Side Marker Lamp
The side marker lamp is located on the outer part of the headlamp, adjacent to the turn signal indicator bulb. The side marker lamp uses an orange colored W3W wedge fitting bulb, which is fitted in a holder which connects with contacts in the headlamp housing. The holder is fitted into an aperture in the headlamp housing and is rotated to lock in position. Access to the side marker bulb requires removal of the headlamp assembly.
The side marker lamp is active at all times when the side lamps are selected on using the lighting control switch. The side marker 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 (central junction box) from a 'lights on' message generated by the AJB.