Part 1

Wipers and Washers

Wiper and Washer System Component Location









GENERAL
The wiper and washer system is controlled by the Central Junction Box (CJB) on receipt of requests made by the driver or the rain/light sensor unit (if fitted). All wiper functions for the front and rear wipers are controlled from a multi-function wash/wipe switch assembly located on the right hand side of the steering column.
The wiper and washer system comprises:
- Front and rear wiper motors
- A front wiper linkage
- Two front and one rear wiper arms and blades
- Two front washer jets and one rear washer jet
- A washer reservoir and pump
- A wash/wipe control column switch.
The following optional items can be added to enhance the wiper system:
- A rain/light sensor for automatic wiper control
- Heated front washer jets
- Headlamp washers
- Low fluid level sensor (fitted to vehicles with headlamp washers).
The wiper system can be optionally equipped with a rain/light sensor. The sensor, located below the interior rear view mirror, detects rain drops on the windscreen and automatically operates the wipers in the intermittent mode. The column stalk switch must be in the intermittent position for rain/light sensor controlled wiper operation.
The front wiper system has five stages of operation and six intermittent delay periods.
The five wiper stages are as follows:
- Flick wipe
- Off
- Intermittent
- Normal (slow) speed continuous
- Fast speed continuous
Speed Control Intermittent Mode
The intermittent, slow and fast speeds are affected by road speed, providing the speed control intermittent wipe mode has been configured. The intermittent wiper delay periods change with the road speed, with the delay decreasing as the road speed increases.
Speed Dependant Wipe Mode
When the speed dependant wipe mode has been configured, the normal continuous operation changes to intermittent operation when the vehicle is stationary. The fast speed operation changes to normal operation when the vehicle is stationary.
The wiper and washers operate with the ignition switch in positions I or II. Wiper functions are suspended during engine cranking to reduce battery power consumption under high load conditions.
Diagnostic information for the wiper system is available and can be retrieved using T4.

CENTRAL JUNCTION BOX
The CJB is an integrated unit located behind the fascia on the passenger side of the bulkhead. The CJB contains fuses, relays and a number of microprocessors, which control the power supply and functionality of the wash/wipe system and other vehicle systems.

Inputs and Outputs
The CJB receives and sends the following wiper and washer system inputs and outputs:





FRONT WIPER ASSEMBLY
The front wiper assembly comprises:
- Wiper motor and linkage assembly
- Wiper arms and blades
- Washer reservoir and pumps.

Wiper Linkage









The wiper linkage and motor assembly are available as separate components. The wiper linkage and motor differs between LH and RH drive models.
The assembly is located below the plenum grill in the engine compartment and is secured with bushes, sleeves and bolts. The rubber bushes isolate the assembly from the body mountings.
The linkage assembly comprises a main tube, with a pivot housing at each end and the motor is attached directly to the tube. A motor crank is positively attached to the motor output shaft. Two link rods then attach to the motor crank which transfers power directly to each pivot crank.
The motor crank converts rotary motion from the motor output shaft into linear movement of the link rods. The cranks, connected between the each link rod and pivot housing, convert the linear motion to reciprocating motion at the pivot housing. This reciprocating motion is passed to the wiper arms and blades causing the blades to wipe an arc across the windscreen.

Wiper Motor
The motor assembly comprises a dc motor, which drives a gear wheel via a worm drive attached to the motor spindle. The gear wheel has a central spigot, which provides the attachment point for the motor crank.
The motor is connected electrically by a five-pin connector. The connector supplies two battery voltage feeds to the motor (when switched). The motor has three sets of brushes with one brush connected to ground. One feed is direct to the motor brush opposite the ground brush and operates the motor at normal (slow) speed. The second feed is connected to a motor brush, which is offset from the ground brush and operates the motor at fast speed. With the power supplied through this brush, the current flows through fewer coil windings. This results in a lower resistance to the current flow to the ground brush and gives a higher motor rotational speed.
Output control of the wiper motor is through a double contact relay. The relay is located in the Battery Junction Box (BJB).
The motor has an internal track switch, which signals the CJB when the wipers have reached the park position. The park signal is closed circuit when the wipers are in the park position. When the wipers are switched off and the CJB receives the park position signal from the motor, the CJB shorts the motor via a relay bridge circuit. This short circuit has the effect of applying a brake to the motor, giving precise positioning of the wiper blades in the park position.

Wiper Arms









The wiper arms are positively located on tapered splines on the wiper linkage spindles.
The wiper arm has a pivot point, midway between the spindle attachment and the blade. A tension spring is connected to the wiper arm on each side of the pivot point and applies pressure to maintain the wiper blade in contact with the windscreen.
The wiper blades are attached to the wiper arms with clips that allow the blade to pivot. The wiper blades comprise of a sprung steel curved backbone which applies the pressure evenly to the windscreen, to which is applied the wiping lip to the bottom surface and an aerofoil section to the top which presses the blades onto the windscreen at high vehicle speeds.

REAR WIPER ASSEMBLY
The rear wiper assembly comprises:
- Wiper motor
- Rear washer pump
- Rear washer jet
- Wiper arm and blade.

Wiper Motor









The rear wiper and washers operation is controlled by the CJB, via the rear wiper relay, which is located in the LH rear 'D' post.
The rear wiper motor is located in the upper tail gate, behind a trim panel. The assembly is secured to the body of the upper tail gate with three M6 nuts. Bushes isolate the motor assembly from the body, which help reduce the transmission of motor operating noise to the tail gate.
The motor is located on a worm drive gearbox mechanism, which converts the rotary motion of the motor output spindle into the required arc for the rear wiper blade.
The feed hose, for the separate rear washer jet, is located at the rear of the motor spindle. The hose is connected to a 90 degrees connector allowing the washer fluid to flow through the centre of the motor spindle. A Non-Return Valve (NRV) is located in the hose, near the motor, and prevents fluid returning to the reservoir.
The motor spindle is a conventional design with a taper spline location for the wiper arm and a threaded shank to secure the arm to the spindle.

Wiper Arm
The wiper arm is similar in design to the front wiper arms. The arm attachment hole has tapered splines, which mate with the splines on the wiper spindle. The arm is secured to the wiper motor spindle with a nut. The wiper arm has a pivot point, close to the spindle attachment. A tension spring is connected to the wiper arm on each side of the pivot point and applies pressure to maintain the wiper blade in contact with the windscreen.
The wiper blade is attached to the wiper arm with a clip that allows the blade to pivot. The blade comprises a number of levers and yokes to, which the rubber wiper blade is attached. The levers and yokes ensure that the pressure applied by the arm tension spring is distributed evenly along the full length of the blade and also allow the blade to adjust to the curvature and contour of the windscreen.
A plastic cap located on the arm pivot point, covers the spindle attachment nut.

WASHER RESERVOIR AND PUMPS









The windscreen washer system comprises:

Vehicles without headlamp washers:
- A reservoir
- A washer pump
- Two washer jets
- Hoses

Vehicles with headlamp washers:
- A reservoir
- Two washer pumps
- A level sensor
- Four washer jets - two windshield and two headlamp washers
- Hoses
The plastic, moulded reservoir is located in the LH wheel arch, behind the liner and has a capacity of 11.08 pints (6.3 liters). It is secured to the body and front panel with bolts. A boss on the reservoir locates in a slot in the front panel and provides additional support.
The reservoir has two recessed holes on its rear face, which provide location for the combined front pump, rear pump and headlamp washer pumps. The pumps are push fitted into grommets, which seal the pumps in their locations. A hole in the top of the reservoir allows for the fitment of a flexible filler tube. The front and rear wash hoses are integrated into the harness and so follow it's routing. The headlamp washer hose comes front the bumper around the bottle to attach to the headlamp washer pump.
A hole with a grommet in the side of the reservoir provides the location for the fluid level sensor.
The low level sensor has a float, with integral magnet. The sensor has a contact, which is normally closed when the reservoir is full. When the fluid level reduces to approximately 1 litre, the magnetic float pivots down, which causes the switch contact to open. This open circuit is sensed by the instrument cluster, which displays the low fluid level message and transmits the switch status on the CAN bus.
The sensor cannot determine the precise amount of fluid in the reservoir, but can detect when the fluid level has fallen below a certain point. When the fluid level is low, the magnetic float closes the sensor contacts, completing a circuit through the sensor. This completed circuit is sensed by the instrument cluster, to which the sensor is directly connected.
The fluid level sensor is monitored continuously by the instrument cluster. The instrument cluster checks the fluid level sensor when the ignition is switched on to give the driver an early warning of the low fluid level. The instrument cluster then monitors the sensor value over a 25 second period when the ignition is on to prevent invalid messages due to fluid 'sloshing' in the reservoir.
When a low fluid level signal is transmitted to the high line instrument cluster, a 'WASHER FLUID LOW' message is displayed in the instrument cluster's message centre. On the low line instrument cluster a low fluid level indicator is illuminated. The first display of this message, or illumination of the indicator, is accompanied by a 'chime' sound to alert the driver to the low fluid level.

HEADLAMP WASHERS









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 energizes the washer pump twice per cycle. The headlamp washer pump is powered for a 0.5 second period.