1998 JAGUAR X308 air condition

Di
sconnect the speed control switch
pack electrical connector, SW02.
1
Meas
ure the resistance between SW
02, pin 06 (BO) and GROUND.
2
Meas
ure the resistance between SW
02, pin 04 (SR) and GROUND.
3
Is either resi
stance
less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to E2
.
E2
: CHECK THE SPEED CONTROL CASSE
TTE REEL FOR SHORT TO GROUND
M
easure the resistance between SW02, pin 06 (at the cassette reel side of the connector) and
GROUND.
1
M
easure the resistance between SW02, pin 04 (at the cassette reel side of the connector) and
GROUND.
2
Is either resi
stance
less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to E3
.
E3
: CHECK THE SPEED CONTROL
ACCEL/SET+ SWITCH ACTION
Meas
ure the resistance between SW02,
pin 06 (BO) and SW02, pin 04 (SR).
1
Op
erate the cruise control
ACCEL/SET+ switch.
2
D
oes the resistance
vary by 430 ohms?
Yes Recheck DTCs. No short found. Po ssible intermittent fault. CLEAR the DTC. TEST the system for
normal operation.
No INSTALL a new speed control switchpack. CLEAR the DTC. TEST the system for normal operation.
P
INPOINT TEST F : DTC P1571;
BRAKE SWITCH MALFUNCTION
WAR
NING: Where tests involve the removal of the steering
wheel, and/or disconnection of air bag connectors, the
procedure for disarming air bags must be followed,
REFER to: Air Bag Supplemental Re straint System (SRS)

(501-20B Supplemental Restra
int System, Description and
Operation).
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
F1: CHECK THE BRAKE

SWITCH TO
ECM CIRCUIT FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1
Di

sconnect the brake switch electrical connector, AC24.
2
D

isconnect the ECM electrical connector, EM10.
3
Meas

ure the resistance between AC24,
pin 01 (US) and EM10, pin 10 (US).
4
Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circui t. For additional information, refer to the wiring diagrams. CLEAR
the DTC. TEST the system for normal operation.
No GO to F2
.
F2: CHECK THE BRAKE
SWITCH TO ECM
CIRCUIT FOR SHORT TO HIGH VOLTAGE
R
econnect the battery negative terminal.
1
Turn the ignition swi

tch to the ON
position.
2
M
easure the voltage between AC24, pin 01 (US) and GROUND.
3
Is th

e voltage greater than 3 volts?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to F3
.
F3: CHECK THE BRAKE
SWITCH TO
ECM CIRCUIT FOR SHORT TO GROUND
Turn the ignition swi
tch to the OFF
position.
1
Meas
ure the resistance between AC24, pin 01 (US) and GROUND.
2

Climate Co
ntrol System - General In
formation - Climate Control System
Description an
d Operation
CAUTION: Observe all relevant safety requirements. Wear suitable eye and skin protection Do not mix HFC 134A and
CFC 12 refrigerants. Do not vent refrigerant directly to atmosphere and always use Jaguar approved recovery, recycle and
recharge equipment. Note the amount of recovered refrigerant; it will indicate the state of the system.
Working Practices
Be aware o
f, and comply with al
l health and safety requirements , whether they be legislative or common sense. This applies
to conditions set both for the operator and workshop.
Before commencing any repair or service procedure, disconnect the vehicle battery ground lead and protect the vehicle,
where appropriate, from dirt or damage.
Work in a well ventilated, clean and tidy area.
Keep all components and tools clean.
Recovery, recycle and recharge equipment must meet, or ex ceed, the requirements detailed in the Specification sub-
section.
Handling Refrigerant

We
ar eye protection at all times. Use gloves and keep all
skin covered that may come into contact with refrigerant.
Should refrigerant come into co ntact with eyes or skin, wash the affected area with cool water and seek medical advice; do
not attempt to treat the condition yourself.
Avoid breathing refrigerant vapor; it may cause irritation to the respiratory system.
CAUTION: Never use high pressure comp ressed air to flush out a system. Under certain ci rcumstances a combination
of HFC 134A refrigerant, compressed air and a source of combus tion (welding and brazing operations in the vicinity), may
result in an explosion and the release of potentially toxic compounds.

HFC 134A and CFC 12 refrigerants must neve r come into contact with each other. They will form an inseparable mixture
which can only be disposed of by incineration.
Do not vent refrigerant directly to atmo sphere; always use Jaguar approved recove ry equipment. Never depress the charge
or discharge port valves to check for the pr esence of refrigerant.
HFC 134A refrigerant is fully recycleable and it may be 'cleaned' by the recovery equipment and therefore re-used following
removal from a system.

Probable
causes of faults may be found by comparing actual
system pressures, registered on your manifold gauge set or
recovery / recharge / recycle station, and the relevant pressure to temperature relationship graph. The following chart
shows the interpretation that ma y be made by this difference.
• NOTE: The A/CCM will disengage the compressor clutch should the evaporator temperature fall to 0°C.
• NOTE: Graphs are typical for HFC 134A
The 'Normal' condition is that which is relevant to the prevailing evaporator temperature.
System Pressure Fault Classification
• NOTE
: If erratic or unusual gauge move
ments occur, check the equipment against a known (calibrated) manifold gauge
set.
This table should be used in conjunction with the graphical representations of 'High side' pressure / ambient temperature
and 'Low side' pressure / evaporator temperature.
Leak
Test
F
a
ults associated with low re
frigerant charge weight and low pressure ma y be caused by leakage. Leaks traced to
mechanical connections may be caused by to rque relaxation or joint face contamination. Evidence of oil around such areas
is an indicator of leakage.
Models that have fluorescent tracer dye incorporated into the refrigeration system can be checke d for non-apparent leaks by
scanning with a high intensity ultraviolet lamp. The location of leaks can be pinpointed by the bright yellow glow of the
tracer dye.
CAUTION: Observe ALL safety precautions associated with ultraviolet equipment.
Should a leak be traced to a joint, check that the fixing is secured to the correct tightening torque before taking any other
action.
When examining the system for leaks, chec k the compressor shaft seal and evaporator.
Charge Re
covery (system depressurization)
The process of
charge r
ecovery will depe
nd on the basic characteristics of your chosen recovery / recycle / recharge
equipment, therefore, follow the manu facturer's instructions carefully.
Remember that compressor oil may be drawn out during this process, take note of the quantity recovered so that it may be
Lo
w side
gauge reading
High s i
de
gauge reading
Fau l
t
Cause
No
r
mal
No
r
mal
Di
sc
harge air initially cool then
warms up
Mois
ture in system
N
ormal
to low
No
r
mal
As aboveAs above
LowLowD
i
scharge air slightly cool
Ref
r
igerant charge low
LowLowDi

scharge air warm
Refr
igerant charge very low
LowLowDi

scharge air slightly cool or frost
build up at expansion valve
Expansion valve st
uck closed
LowLowDi

scharge air slightly cool,
sweating or frost after point of restriction
Restri
ction in High side of system
HighLowCompressor noisyDe
fe
ctive compressor reed valve
HighHighD
i
scharge air warm and high side
pipes hot
Refri
gerant charge high or inefficient condenser
cooling due to air flow blockage or engine cooling fans
not working
HighHighD i
scharge air warm / Sweating or
frost at evaporator
Expans ion valve st
uck open

re
placed.
E

vacuating the System
This process, the removal
of un
wanted air and moisture, is crit ical to the correct operation of the air conditioning system.
Moisture in the system can be highly de structive and may cause internal blockages due to freezing; water suspended in the
lubricating oil will dama ge the compressor. Once the system has been dismantled, or the refrigerant charge recovered, all
traces of moisture must be removed before recharging.
Specific procedures will vary depending on the individual characteristics of the recovery / recycle / recharge equipment, and
must be carried out exactly in accordance with the manufacturer 's instructions. However, it is recommended that initially
only the high-side valve be opened at the start of the procedure. After a short time a small depression should be seen on
the low-side, at which point the low-side valve may be opened and the evacuation process completed. If a vacuum is not
registered on the low-side, it may indicate that the expansion valve is permanently closed or that the system is blocked.
This simple check may save time and effort when the system is recharged.

Climate Control System - General Informatio
n - Climate Control System
D
iagn
osis and Testing
I
n
troduction
It is very i
m
portant to positive
ly identify the area of concern before starting a rectification procedure. A little time spent with
your customer to identify the conditions under which a pr oblem occurs will be beneficial. See below for example:
Sym
ptom Chart
Re
lev
ant criteria are: Weather conditions,
ambient temperature, intermittent or cont inuous fault, airflow fault, temperature
control fault, distribution fault and air inlet problem.
Functio n
al Check
This
s
imple 'first line check' will allo
w you to ascertain whether the system is operating within its design parameters, withou t
recourse to PDU.
1. 1. With the engine at normal running temperature.
2. 2. Presss AUTO to display selected temperature and illuminate AUTO and A/C state lamps.
3. 3. Rotate FAN to increase or decrease lowe r speed, verify bar graph representation.
4. 4. Select A/C to toggle on or off. (T he compressor may be inhibited by the ECM should either the engine
temperature NOT be normal or the ambient be < 2° C).
5. 5. Select RECIRC , state lamp should be lit and the recirculation flaps open.
6. 6. Select distribution butt ons in turn, verify correct air distribution and relevant state lamp.
7. 7. Select DEFROST , check max fans and air to the windshield.
8. 8. 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.
9. 9. Select EXT to toggle between am bient and control temperatures.
10. 10. Select F (where fitted) and R - noting exterior mirror; verify timer and operation (glass may be warm to the
touch)
11. 11. Initiate system 'Self Test' to display stored faul ts should any of the above not perform as stated.
Sy
stem Symptoms
There
are five
basic symptoms associated
with air conditioning fault diagnosis.
The following conditions are not in order of priority.
Sy m
ptom
Possib
l
e Sources
Acti
o
n
N
o defrostN o
airflow to windshield
*
Check blower s and flaps
*
N o functi
on in defrost mode
*
Check A/CCM
*
Mo de s
election not available
*
Chec k
control panel communication
*
Ai rfl
ow OK but no heat
*
Check water pu
mp and valve
*

Sym
ptom #2
Sy
mptom #2
Sym

ptom #3
Sy
mptom #3
No
cooling
Compressor sei
zed
Compressor seal failure
Compressor valve or piston damage
*
*
*
R
enew compressor
*
Compressor cl
utch / circuit faulty
*
R
efer to PDU
*
D
rive belt slack / broken
*
Adjust or r
enew
*
B
lower motor / circuit faulty
Pressure switch / circuit fault
*
*
R
efer to PDU
*
Total l
oss of refrigerant caused by broken pipe or joint
*
Repair / renew. Check code 2
3
*
P
artial loss of refrigerant caused by leaking joint or pipe
*
R
epair / renew, check fault code #23
*
Conden
ser damage
*
Re
new, check fault code #23
*
Bl
ocked receiver / drier filter
*
R
enew receiver / drier
*
Evaporator senso
r / circuit faulty
*
R
efer to PDU, check fault code #13
*
Bl
ocked pollen filter (if fitted)
*
Cle
an or renew
*
• NOTE: Should a leak or low refrigerant be established as the cause of INSUFFICIENT COOL ING, follow the procedures
Recovery / Recycle / Recharge, this section, and ob serve all refrigerant and oil handling instructions.
Sy
mptom
Possib
le Sources
Acti
on
Insuffi

cient
cooling
Compre
ssor clutch slipping
*
R
enew clutch assembly
*
Fl
aps or vents closed / seized
*
Check f
ault codes #41 to 46
*
Bl
ower circuit fault
*
R
efer to PDU
*
Bl
ocked condenser matrix / fins
*
Check hig
h / low side pr
essures / renew. Check /
clean fins
*
Bl
ocked evaporator matrix
*
Check hig
h / low side
pressures / renew
*
Bl
ocked pollen filter (if fitted)
*
Cle
an or renew
*
Evaporator temp
erat
ure sensor faulty
*
R
efer to PDU
*
P
artial loss of refrigerant caused by leaking joint

or pipe
*
R
epair / renew
*
Blocked expan
sion valve
*
Check hig
h / low side
pressures / renew
*
Expans
ion valve fault
*
Chec
k system pres
sure differential
*
C
ollapsed air conditioning hose hose
*
Check hig
h / low side
pressures / renew
*
Moi
sture or air in the system
*
Chec
k system pressures
*
Low r
efrigerant charge
*
Initiate recovery
procedure, check fault code #23
*
Coo
lant flow valve open
*
Chec
k operation
*
Sy
mptom
Possib
le Sources
Acti
on
Int

ermittent cooling
Compre
ssor clutch slipping
*
R
enew clutch assembly
*
Compressor cl
utch circuit faulty
Blower(s) circuit faulty
*
*
R
efer to PDU
*
Motorized in-car aspirator faulty

*
R
efer to PDU, check fault code #11
*
Evaporator temp
erature sensor faulty

*
R
efer to PDU, check fault code #13
*
Bl
ocked condenser matrix / fins
*
Check hig
h / low side pressures / renew. Check / clean fins

*
Bl
ocked evaporator matrix
*
Check hig
h / low side
pressures / renew
*


Sym
ptom #1
Sy
mptom #1
Sy

mptom
Possib
le Sources
Acti
on

Climate Co
ntrol System - General In
formation - Air Conditioning (A/C)
System Check - Re tail Procedure
Gen
eral Procedures
E

vacuating the Manifold Gauge Set
Connecting the Manifold Gauge Set
C
AUTION: Only use hoses with connectors wh
ich are dedicated to HFC 134A charge ports.
Stabilizing the System

1.
At
tach the center (service) hose to a vacuum pump and start
the pump. Open fully both high and low valves and allow the
vacuum to remove air and mois ture from the manifold set for
at least five minutes.
CAUTION: It is imperative th at the vacuum pump is not
subjected to a positi ve pressure of any degree. Therefore the
pump must be fitted wi th an isolation valve at the center (service
hose) connection and this valve mu st be closed before the pump
is switched off. This operation replaces the 'purge' procedure used
on previous systems. Observe the manufacturer's
recommendation with regard to vacuum pump oil changes.
Turn the vacuum pump off and isol ate it from the center service
hose but do not open the hose to atmosphere.
1. Att
achment of the hose quick release connectors to the high
and low side system ports is stra ightforward, provided that the
high and low valves are closed and the system is NOT
operational.
WARNING: UNDER NO CIRCUMSTANCES SHOULD THE
CONNECTIONS BE MADE WITH THE SYSTEM IN OPERATION OR
THE VALVES OPEN. SHOULD THE VALVES BE OPEN AND A
VACUUM PUMP OR REFRIGERANT CONTAINER ATTACHED, AN
EXPLOSION COULD OCCUR AS A RESULT OF HIGH PRESSURE
REFRIGERANT BEING FORCED BACK INTO THE VACUUM PUMP OR
CONTAINER.
Assessment of system operating efficiency and fault
classification may be achieved by using the facilities on your
Recovery / Recharging / Recycling station, follow the
manufacturer's instructions implicitly and observe all safety
considerations.
1. Accurate test gauge data wi
ll on
ly be attained if the system
temperatures and pressures are stabilized.
E
nsure that equipment and hoses cannot come into
contact with engine moving parts or sources of heat.
It is recommended th at a free standing air
mover is placed
in front of the vehicle to provide air flow through the
condenser / cooling system.
St
art the engine, allow it to attain normal working
temperature and set at fast idle (typically 1200 to 1500
rpm).


Select full

air condit
ioning performance.
With
all temperatures and pres
sures stable, or displaying
symptoms of faults; begin relevant test procedures.

Climate Control System - General Infor
mation - Air Conditioning (A/C)
System Recovery, Evacuation and Charging
Gen e
ral Procedures
Recover / Reclaim
Ev
acuation
Charging

1.
CAUTIO
N: Read the procedures and instructions supplied
by the manufacturer of the air co nditioning service center before
commencing any process requiring the handling of refrigerant. In
addition to the manufacturer's in formation, observe all safety
precautions and advice deta iled in this section.
Disconnect battery ground lead; refer to 86.15.19.
2. Remove passenger side fi
rewall cover.
3. Remove driver side firewall cover.
4. Remove engine compar tment rear cover.

5. Re
move vehicle charge port
protective caps and connect
equipment pressure hoses to vehicle.
1. BLUE hose = low pressure.
2. RED hose = high pressure.
6. Complete procedure in ac cordance with equipment
manufacturer's instructions.
1. Complete procedure in ac cordance with equipment
manufacturer's instructions.
This proc
ess will typically ta
ke 30 minutes, but will depend
upon the equipment and the ex tent of repairs carried out
to the system.
1. Set the appropriate charge weight, see Specifications in this
section.
2. Complete procedure in ac cordance with equipment
manufacturer's instructions.
3. Disconnect hoses from vehicle and replace charge port
protective caps.
4. Reconnect battery ground lead; refer to 86.15.15.
5. Check system for correct operation.