air filter JAGUAR XJ6 1994 2.G User Guide

Climate Control Systems
14.8 REFRIGERATION CYCLE:
The Compressor draws low pressure, low temperature re- frigerant from the evaporator and by compression, raises re- frigerant temperature and pressure. High pressure, hot
vaporized refrigerant enters the Condenser where it is
cooled by the flow of ambient air.
A change of state occurs
as the refrigerant cools in the condenser and it becomes a
reduced temperature high pressure liquid.
From the condenser the
liquid passes into the Receiver / Drier which has three functions,
a) Storage vessel for varying system refrigerant demand.
b) Filter to remove system contaminants. c) Moisture removal via the dessicant.
With the passage through the
receiver/drier completed the,
still high pressure liquid refrigerant enters the Expansion
Valve where it is metered through a controlled orifice which
has the effect of reducing the pressure and temperature.
The refrigerant, now
in a cold atomized state, flows into the
evaporator and cools the air which is passing through the
matrix.
As heat is absorbed by the refrigerant
it once again changes
state, into a vapour, and returns to the compressor for the
cycle to be repeated (Fig.
1).
There is an automatic safety valve incorporated in the com- pressor which will operate should the system pressure be in
excess of 41 bar. The valve will reseat when the pressure
drops below 27,6 bar.
W Thedivisionof HIGHandLOWsideissimplythesys- tem pressure differential created by the compressor
discharge (pressure), suction (inlet) ports and the
relative inlet and outlet ports
ofthe expansion valve.
This differential is critical to system fault diagnosis
and efficiency checks.
Twelve Cylinder Vehicles only:
Dual pressure switch: This two-function pressure switch
cuts electrical power to the compressor clutch if the system
pressure is outside of the range
of 2 Bar (1st Function) to 30
Bar (2nd Function).
Six Cylinder Vehicles only:
There are two switches incorporated into the high side of the
system which have the following functions:
a) Trinary; This three function pressure switch, cuts electri
-
cal power to the compressor clutch should the system pres- sure not be in a range of 2 bar (1st function) to 30 bar (2nd
function). The switch also provides a ground signal to oper
- ate the appropriate relay (within the 'Stribel,' unit) to ener- gize both engine cooling fans when maximum A/ C cooling
is required. Operation pressure, 20 bar input (3rd function).
b) Pressure Switch Slow Cooling Fans; When the system
pressure is 12 bar, medium A/ C demand, the operation of
this switch connects both engine cooling fans in series to op- erate at half battery voltage and so, half fan speed. 1.
Compressor
2. Condenser
3. Receiver / Drier 4. Expansion Valve
5. Evaporator
6. Pressure switch - Dual type
on 12
cyl & Trinary on 6 cyl
Fig. 1
0
0
Issue 1 August 1994 12 X300 VSM

Climate Control Systems
14.10 FAULT DIAGNOSIS
14.10.1 Introduction
It is very important to positively identifythe area of concern before starting a rectification procedure. A little time spent
with your customer to identify the conditions under which a problem occurs will be beneficial. Relevant criteria are:
Weather conditions, ambient temperature, intermittent or continuous fault, airflow fault, temperature control fault, dis
- tribution fault and air inlet problem.
14.10.2 Functional Check
This simple 'first line check' will allow you to ascertain whether the system is operating within its design parameters,
without recourse to (JDE). Please carry out the following, in order.
0 Start engine and attain normal running temperature.
0 Presss AUTO to display selected temperature and illuminate AUTO & AJC state lamps.
0 Rotate FAN to increase or decrease lower speed, verify bar graph representation.
0 Operate AJC to toggle on or off. Because the compressor can be inhibited by the engine management system,
ensure that the engine temperature is normal and that the ambient is above 5O C.
0 Operate RECIRC, state lamp should be lit and the flap behind the blower grille open.
0 Operate distribution buttons in turn, verify correct air distribution and relevant state lamp.
0 Operate DEFROST, check max fans and air to front screen.
0 Cycle TEMPERATURE to 'Hi' and 'Lo' to verify demanded variations and display operation. Note that extremes
will provide max heat or cold independent of in-car temperature.
0 Operate EX to toggle between ambient and control temperatures.
0 Operate HFS and HRW to note timer and mirror operation.
0 Initiate System Self Test to check for, and extract, stored faults should any of the above not perform as stated.
14.10.3 System symptoms
There are five basic symptoms associated with air conditioning fault diagnosis. The following conditions are not in order of priority.
No Cooling
0 Is the electrical circuit to the compressor clutch functional?
0 Is the electrical circuit to the blower motor(s) functional?
0 Slack or broken compressor drive belt.
0 Compressor partially or completely seized.
0 Compressor shaft seal leak.
0 Compressor valve or piston damage (may be indicated by small variation between HIGH &LOW side pressures
relative to engine speed).
0 Broken refrigerant pipe (causing total loss of refrigerant).
0 Leak in system (causing total loss of refrigerant) - possible code 23.
0 Blocked filter in the receiver drier.
0 Evaporator sensor disconnected - possible code 13.
0 Pressure switch faulty - possible code 23.
X300 VSM Issue 1 August 1994

Climate Control Systems
lnsufficent Cooling
0 Sluggish blower motor(s).
0 Restricted blower inlet or outlet passage
0 Blocked or partially restricted condenser matrix or fins.
0 Blocked or partially restricted evaporator matrix.
0 Blocked or partially restricted filter in the receiver drier.
0 Blocked or partially restricted expansion valve.
0 Partially collapsed flexible pipe.
0 Expansion valve temperature sensor faulty (this sensor is integral with valve and is not serviceable).
0 Excessive moisture in the system.
0 Air in the system.
0 Low refrigerant charge - possible code 23.
0 Compressor clutch slipping.
0 Blower flaps or distribution vents closed or partially seized - possible codes 41 or 46.
0 Coolant flow valve not closed.
0 Evaporator sensor incorrectly positioned
m: Should a leakor low refrigerant be established as the cause of /NSUff/C/€NTCOOL/NG,followthe procedures
Recovery / Recycle / Recharge, this section, and observe all refrigerant and oil handling instructions.
lntermiffent Cooling
0 Is the electrical circuit to the compressor clutch consistent?
0 Is the electrical circuit to the blower motor(s) consistent?
0 Compressor clutch slipping?
0 Motorized in-car aspirator or evaporator temperature sensor faulty, causing temperature variations - possible
codes 11 or 13.
0 Blocked or partially restricted evaporator or condenser.
Noisy System
0 Loose or damaged compressor drive belt.
0 Loose or damaged compressor mountings.
0 Compressor oil level low, look for evidence of leakage.
0 Compressor damage caused by low oil level or internal debris.
0 Blower motor(s) noisy.
0 Excessive refrigerant charge, witnessed by vibration and 'thumping' in the high pressure line (may be indicated
by high HIGH & high LOW side pressures).
0 Low refrigerant charge causing 'hissing' at the expansion valve (may be indicated by low HIGH side pressure).
0 Excessive moisture in the system causing expansion valve noise.
0 Air-lock in water pump*.
lnsufficent Heating
0 Coolant flow valve stuck in the closed position.
0 Motorized in-car aspirator seized.
0 Cool air by-pass damper stuck or seized - possible code 43.
0 Blocked or restricted blower inlet or outlet.
0 Low coolant level.
0 Blower fan speed low.
0 Coolant thermostat faulty or seized open.
0 Water pump inoperative or blocked
0 Air-lock in matrix*.
m: * Please see Sections 4.1 and 4.2 for specific coolant fill / bleed procedures.
Electrical faults may be more rapidly traced using
(JDE), please refer to the (EDM).
Issue 1 August 1994 16 X300 VSM

15.6
15.6.1
The single windscreen wiper blade is controlled by a windscreen wiper/washer switch located on the right-hand side
of the steering column switchgear (see Fig.
1).
POWER WASH & SCREEN WASH/ WlPE
Windscreen Washers & Wipers, General Description
The windscreen wiper motor, part of the wiper motor
assembly operates at slow or fast speeds and drives the
lever assembly, a single arm and blade via a crank.
On
V12 engined vehicles the wiper motor assembly is
mounted to the front of the bulkhead with the motor
protruding into the plenum chamber, whilst on AJ16 engined vehicles the wiper motor assembly is mounted into
the same position, but with the motor protruding into the
engine compartment.
For wipe and wash operation
a mixture of water and special
'Jaguar Windscreen Fluid' is drawn from the PVC reservoir
assembly by
two electrically controlled pumps and is then
distributed via flexible feeder hoses interconnected using
'TEE' pieces to the screen wash jets and to heated power
wash jets (where fitted). The ends of power wash hoses are
fitted with 'quick
fit' fluid connectors.
The
two pumps, one for screen wash and one for headlamp
power wash are externally fitted to the reservoir located at
the front right
-hand side of the engine compartment.
Contained within the reservoirs pull-up neckis a serviceable
filter.
The screen wash jets with independently adjustable
eyeballs are mounted on the plenum chamber finisher and
the temperature of the fluid passing through the jets is
controlled from an ambient temperature sensor fitted near
the inlet of the right
-hand side air duct. Fig.
1
The
fluid temperature for each of the headlamp wipe wash operation is controlled by self regulating, heated power
wash jets mounted on to either side of the bumper.
Each powerwash jet is protected by
a cover supplied with an integral cover-to-bumperseal. The cover snap fixes into
the bumper.
15.6.2
This switch only operates with the ignition switch in position '11' and has the following functions:
windscreen Wiper and Washer Switch
Position 0 The wind screen wiper is switched 'OFF' and parked.
Position 1: Normal speed wiper operation is obtained by pushing the switch lever up one position.
Position 2: High speed wiper operation is obtained by pushing the switch lever fully up.
Position D: To obtain intermittent wiper operation the switch lever is pushed down and released.
The delay period will vary with vehicle speed. To cancel the function repeat the procedure.
15.6.2.1 Single Wipe Operation
To obtain a single sweep of the wiper blade, the lever is pulled towards the steering wheel and released.
W The intermittenmick wipe operations are both at slow speed and they are controlled by a Central Control
Module (CCM), which also controls the headlamp power wash operation.
Issue 1 August 1994 X300 VSM

Systems Repair Body & Body -
A4.1.3. POTENTIAL RISKS I
A4.1.3. Paint
Organic solvents, found in paints, may cause damage or severe irritation to liver, kidneys, digestive tracts and respira- tory system if inhaled over long periods of time.
Prolonged exposure to isocyanates may cause lung sensitization. Asthma
-like symptoms may develop with subse-
quent exposure to very low concentrations of isocyanates.
Solvent inhalation can cause dizziness or loss of consciousness.
Splashes of solvents, paint activators and additives can cause damage to the eyes and may cause dermatitis. Peroxide
and acid catalysts may cause burns.
Inhalation of
spray dust and sanding debris may cause lung damage.
I
A4.1.3.2 Applied Heat (Welding)
There is considerable risk of damage to eyes and skin when welding or flame cutting.
Fire is a serious danger and many materials or fluids within the vehicle are highly flammable.
Toxic and dangerous fumes may be liberated when any of the following are subjected to heat:
0 Expanded foam
0 Corrosion protection
0 Trim and seat materials
0 Paints which contain isocyanates
0 Adhesive and sealing compounds
When heated to a temperature of 3OO0C, polyurethane based compounds may liberate small quantities of isocyanate.
Many types of nitrogen containing chemicals may be liberated as breakdown products; these chemicals can contain
isocyanates, oxides of nitrogen and hydrogen cyanide.
Potentially toxic or asphyxiant fumes and gases are produced by welding, for example; zinc oxide with zinc coated
panels, and ozone gas from the MIG process.
A4.1.3.3 Metal Repair
There is considerable risk of damage to eyes, ears and skin when metal cutting, forming, or dressing is being carried
out.
Soldering may be hazardous because of heat generated fumes and skin contact with the materials.
A4.1.4. PRECAUTIONS
A4.1.4.1 Paint
The inhalation of sprays, fumes, or dust during paint application or sanding processes should always be avoided. En- sure that there is efficient ventilation / extraction at all times. Paint spraying should be confined as far as possible to
spray booths. Personnel with a history of asthma should not be engaged in any process which involves the use of
isocyanates. Any operator working inside
a spray booth where isocyanate material is present must use air-fed breath- ing equipment. Supplied air to the visor should be fed at the recommended pressure and filtered to remove oil, water,
and fumes. Operators involved in handling mixing or spraying should wear protective clothing - gloves and goggles,
to avoid skin and eye contact.
A particle mask or canister type respirator should be worn when sanding.
A4.1.4.2 Applied Heat
When welding, flame cutting, brazing etc, the operator should use as appropriate, goggles, mask/fume extractor and
flameproof protective clothing. It is especially important when working with polyurethane compounds to use air-fed
breathing equipment.
Ensure that
at all times the appropriate fire fighting equipment is available and that personnel are trained in its use.
A4.1.4.3 Metal Repair
Appropriate eye and hand protection should be worn when sanding, drilling, cutting, chiselling, flatting or welding.
Operators should wear
a face mask or air-fed visor when sanding or flatting either body solder or fillers.
When
a soldering operation has been completed, swarf must be removed from the work area and the operator must
wash his hands thoroughly.
X300 VSM 3 Issue 1 August 1994