LR3/Disco 3
The headlamp washer assembly is located below each headlamp.
The headlamp washer operation is controlled by the CJB via a headlamp washer relay. The relay is located in the Battery
Junction Box (BJB).
Head Lamp Wash Only (No Wipe Function)
The headlamp washers are only active when the headlamps and ignition are switched on. If the washer reservoir fluid
level becomes low, the instrument cluster sends a message, via the CAN bus, to the CJB, which suspends headlamp
wash operation to preserve washer fluid in the reservoir.
With the ignition and lights on, headlamp wash is activated on the first operation of the wiper column control switch in the
wash/wipe position. The CJB then suspends headlamp wash activation for the next 10 minutes and four operations of the
wash/wipe switch.
The CJB monitors the operation of the wash/wipe switch and maintains a counter to restrict headlamp washer operation
to every fourth operation of the wash/wipe switch in conjunction with a 10 minute timer. The timer prevents a second
operation of the headlamp washers within a 10 minute period. Should the washer switch be activated for more than four
programmed wipe requests during the 10 minute period, the headlamp washer will remain disabled. Only the next
consecutive programmed wipe request, after the 10 timer has expired, will the headlamp washers be enabled. The
counter and timer are reset when the ignition is switched off.
When headlamp wash is active, the CJB energises the washer pump twice per cycle. The headlamp washer pump is
powered for a 0.5 second period.
RAIN/LIGHT SENSOR
2
Reservoir
3
Washer fluid tube
Item Part Number
Description
1
Adhesive pad
2
Optical element
3
Sub-assembly light guide
