1994 JAGUAR XJ6 clutch

12.3 BRAKE FLUID LEVEL CHECK
WARNING: AVOID SKIN / EYE CONTACT OR INGESTION OF BRAKE FLUID. IF SKIN OR EYES ARE ACCIDENTALLY
SPLASHED WITH BRAKE FLUID, RINSE THE AFFECTED AREA IMMEDIATELY WITH PLENTY OF WATER
AND SEEK MEDICAL AlTENTlON IMMEDIATELY.
Checking the fluid level
CAUTION: Fluid must not be allowed to contact the vehicle paintwork. Remove any spilt fluid from the paintwork
by rinsing away with running water. Methylated spirit (denatured alcohol) must not be used to clean the contaminated area.
Correct brake fluid level is essential for the efficient oper- ation of the brake system. Check that the fluid level is be- tween the MAXand MIN marks on the fluid reservoir (Fig. 1). Top up if necessary with recommended brake fluid.
BMQ: The efficiency of the brakes may be impaired if fluid
is used which does not meet specifications. Use
ONLY brake and clutch fluid that conforms to
a mini- mum DOT 4 specification. Also do not use brake
fluid that has been exposed to atmosphere for any
length of time. Moisture absorbed from the atmos
- phere impairs the efficiency of the brake fluid.
JLX- 081
Fig. 1
Issue 1 August 1994 18 X300 VSM

Climate Control Systems
Manual Inputs
Automatic inputs
outputs
14.5 AIR CONDITIONING CONTROL MODULE (A/CCM)
14.5.1 Description
Theclimate control system peripheralscommunicate with theA/CCMvia three main devicecategories, plusthevehicle
power supply and ground connections.
Control panel Face Vent Temperature Control
Temperature and solar sensors
Flap
servo motor potentiometers
Circulation pump
& coolant flow valve
Power
transistor(fan speed control)
Compressor lock sensor
(12 cylinder only)
Instrument pack (coolant temp
& road speed) (engine revolutions via engine control module)
Blower motors (Left
& Right) & associated relays
Flap
servo motors
Heated front
/ rear screens & exterior mirror relays
Motorized in
-car aspirator
Compressor clutch request to engine control module (not
heater-only cars)
Circulation pump relay
Coolant flow valve
X300 VSM Issue 1 August 1994 7

Climate Control Systems
CONTROL MODULE FAULT & CONDITION SELF-ANALYSIS
0 14.6 14.6.1 System Health
The climate control system has a 'self-test' facility, accessible from the control panel. The self test sequence has two
basic modes:
0 System error information is stored in the A/CCM up to a maximum of five faults. Should a fault occur there will
be an audible 'beep' and the message 'Er' will be displayed on the control panel LCD for approximately five (5)
seconds after ignition on. Please note that this will happen only once in any ignition switch cycle. The error
source may be accessed by the procedure described in 'Self Test System Diagnosis', this section.
0 Panel communication check may be initiated by following the instruction in 'Self Test System Diagnosis', this
section.
Nsfe: Displayed error codes are NOT directly related to Jaguar Diagnostic Equipment (JDE) but more detailed fault
related information may be accessed using Portable Diagnostic Unit (PDU).
14.6.2 System Protection
Power to the compressor clutch may be cut should either the engine management or air conditioning control systems
detect certain conditions; these conditions may be caused by Fault or Demand and can be classified thus:
0 Engine coolant overheat,
0 Refrigerant excessive pressure.
0 Refrigerant, insufficient pressure or low charge weight.
0 Speed differential between compressor and crankshaft caused by belt slippage or compressor seizure (indi-
cated by A/C state lamp flashing once per second) - 12 cylinder engine only. This feature, 'lock sensing' is fully
explained
in the EDM.
Demand
0 Engine maximum power requirement
0 Electrical system drain at engine idle.
X300 VSM 9 Issue 1 August 1994

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

Climate Control Systems
Action
Simultaneously hold AUTO and RECIRC - Switch
ignition to ON
Press AUTO
Press FACE
Simultaneously press FACE and HRW
Press
RECIRC (Press FAN to skip actuator check)
Press FAN
14.11 SYSTEM SE1 F-TEST
14.11. I Interrogation Procedure via the Control Panel
Result
Display element check
Any stored fault NUMERIC code
(If ZERO appears there are
no stored codes)
Scroll through stored faults (maximum of
5)
Clear stored fault codes (may need to be repeated for each
fault)
Initiate actuator check (Actuator codes
20 through 27*)
Exit error check mode
Fault Code
0
11
12
13
14
15
21
22
0
23
14.1 1.2 Control Panel Fault Code Key
Item Description
Normal Operation No
fault codes present, wait 30 seconds for system self-
check.
Motorized In
-car Aspirator Open /short in sensor circuit. Panel fault codes are not stored
for motorized in
-car aspirator motor failure.
Ambient Temperature Sensor Open
/ short circuits.
Evaporator Temperature Sensor Open
/ short circuits.
Water Temperature Input Instrument pack output.
Heater Matrix Temperature Sensor Open
/ short circuits.
Solar Sensor Open
/ short circuits.
Compressor Lock Signal
- 12 cylin- Open /short circuits. Low gas charge, low compressor oil,
der and supercharged
6 cylinder loose belt.
engines only.
Refrigerant Pressure Switch Open /short circuits. Low gas charge*
31
32
33
34
35
36 0
I 24 1 Face Vent Demand Potentiometer. 1 Open / short circuits
LH Fresh
/ Recirc. Potentiometer
RH Fresh / Recirc. Potentiometer
cool ~i~ by-pass potentiometer
Defrost Vent Potentiometer
Centre Vent Potentiometer
Foot Vent Potentiometer Open
/short circuit
in potentiometer. feed.
w: and log further faults. Cycling the ignition two or three times
after rectification of the fault will cure this.
In certain circumstances, the motor can over-travel
43
44
I Defrost Vent Motor
I Cool Air by-pass Motor
I 41 I LH Fresh / Recirc. Motor I
Check for short / open circuits in motor drive lines. Motor flap
sticking
/ jammed.
1 42 I RH Fresh / Recirc. Motor I
1 45 I Centre Vent Motor I
46 I Foot Vent Motor
w: In ambient temperatures below Oo C, the system may log fault code 23 because the low ambient causes a tem-
porary low gas pressure. Where the ambient temperature rise above 40" C, and if the engine is close to over- heating, feed to the compressor clutch may be cut and code 23 registered.*
X300 VSM 17 Issue 1 August 1994

Black
Black
Black All
models
All Models
All Models
Black
Black All
Models
All Models
Black/
White Stripe
Black/
White Stripe
Black Non
Aircon.
Models
only
Non Power
Wash Models
only
Optional
0 Key to Fig. 1, hgine Compartment Relays, page 14.
Number v12 Color
All Models
SRO
B6.55.04
Rdaw
Horn
Location
Engine
compartment,
inside the left
hand side fuse box.
Engine
compartment,
behind left hand head
lamp assembly.
see starter
motor
solenoid. All
Models
1 ~~
All
Models 5 Starter Motor
Solenoid
4 All Models
All Models 18.30.34 Air-conditionin
g Water Pump
Wiper Motor
On
/Off
2 see starter
motor
solenoid.
see starter
motor
solenoid. All
Models
3 Wiper Fast /
Slow
18.30.71 Engine
compartment, behind right
hand head
lamp assembly. 8 EMS Engine
Management
System
Control
Black
I
All Models 9 Ignition Coil
PI Main Relay see
EMS
control.
see EMS
control. Black
I
All
Models 8
Air Pump 7 see EMS
control.
see EMS
control. Black
Air Injection
Black Air Con
- Model Air
Injection
only
All Models
18.30.34
86.55.08 Air
Conditioning
Compressor
Clutch
Relay Case
Engine
compartment,
on the right
hand side inner
wing valance.
Relay
Case Non Power
Wash
Models
only
11
10
12
Power Wash
Screen Wash Optional
All Models
All Models
Black
All Models
Ignition Relay
Engine
compartment,
inside
right
hand fuse box.
X300 VSM 33 Issue 1 August 1994