1994 JAGUAR XJ6 lock

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.
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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).
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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.*
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Climate Control Systems
No heat
One vent failing to open
/ close
Poor airflow
14.11.3 Associated Faults
Other symptoms that may exist without storing fault codes:
Airlock in system.
Electric water
pump inoperative
Coolant flow valve stuck closed
Faulty engine coolant thermostat
Broken linkage.
Blower motors
- incorrect operation
14.11.4 Panel Communication Check
Action Result
Panel communication
with FACE, FOOT & FACE, FOOT,
SCREEN
& FOOT, DEFROST, RECIRC lines checked - State lamps will illuminate if all is OK. Unlit state lamp
means continuity fault for that specific link. See EDM
for
full check.
0
0
0
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Climate Control Systems
14.12 MANIFOLD GAUGESET
The manifold gauge set is a most important tool fortracing faults and system efficiency assessment. The relationship
to each other of HIGH and LOW pressures and their correlation to AMBIENT and EVAPORATOR temperatures must be
compared to determine system status (see Pressure /Temperature graphs in Sub
-Sections 14.14 & 14.15).
Because of the heavy reliance upon this piece of equipmentfor service diagnosis, ensure that the gauges are calibrated
regularly and the equipment is treated
with care.
3
1 Low side service hose - BLUE
5 High side hand valve - RED 2 Low side hand valve - BLUE 6 High side service hose - RED
3 Low pressure compound gauge - BLUE 7 System service hose - NEUTRAL
4 High pressure gauge - RED
COLOUR (commonly yellow)
Fig. 1 Manifold gauge set
Manifold.
The manifold is designed to control refrigerant flow. When connected into the system, pressure is registered on both
gauges at all times. During system tests both the high and low side hand valves should be closed (rotate clockwise
to seat the valves). The hand valves isolate the low and the high sides from the centre (service) hose.
0 Low side pressure Gauge.
This compound gauge, is designed to register positive and negative pressure and may be typically calibrated - Full
Scale Deflection, 0 to 10 bar (0 to 150 Ibf / in2) pressure in a clockwise direction; 0 to 1000 mbar (0 to 30 in Hg) FSD
negative pressure in a counter clockwise direction.
High Side Pressure Gauge.
This pressure gauge may betypicallycalibrated from 0 to30 bar (0 to 500 Ibf/in2) FSD in a clockwise direction. Depend-
ing on the manufacturer, this gauge may also be of the compound type.
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Climate Control Systems
High Side Gauge
Normal
@ 14.16 SYSTEM PRESSURE FAULT CLASSIFICATION
This table should be used in conjunction with the graphical representations of 'High side' pressure / ambient tempera- ture and 'Low side' pressure / evaporator temperature, this section.
Fault Cause
Discharge air initially cool then Moisture in system
warms up
1 Low Normal
Low
Low
Low
Low
I Low
As above As above
Discharge air slightly cool HFC
134A charge
low
Discharge air warm HFC
134A charge very low
Discharge air slightly cool or frost Expansion valve
stuck closed
build up
at expansion valve
Discharge air slightly cool, sweat
- Restriction in High side of
ing or frost
after point of restriction system
I
Low
High
High
I
Compressor noisy Defective compressor
reed valve
Discharge air warm and high side HFC
134A charge
high or
pipes hot inefficient
condenser cooling
dueto
air flow blockage or engine cooling
fans not working
Expansion valve stuck open
Discharge air warm
Sweating or frost
at evaporator
If erratic or unusual gauge movements occur, check the equipment against a known (calibrated) manifold
gauge
set. ~ ~~~
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15.1.2 Handling Undeployed Modules
The electrically-activated airbag module contains sodium azide and sodium nitrate which are poisonous and
extremely flammable substances.
Their contact with acid, water or heavy metals may produce harmful and irritating gases or combustible compounds.
The airbag module is
non-serviceable and must not be dismantled, punctured, incinerated or welded.
WARNING: DO NOT ATTEMPT ANY REPAIRS TO THE AIRBAG MODULE.
Never measure the resistance of the airbag module, as this may cause the airbag to deploy. Suspect modules must be returned to Jaguar Cars Ltd. or their importer for replacement.
Tampering or mishandling can result in personal injury.
Keep away from heat, sparks and open flames. Do not store
at temperatures exceeding 93O Celsius (200OF).
Keep away from electrical equipment as electrical contact may cause ignition.
Do not drop or impact airbag module.
Always position module 'cover
-up'.
Ensure that the connector is protected to prevent damage.
J76-1058
Fig. 1 The Driver-side Airbag
Store modules in a secure lockable cabinet.
Never position projectile material over the undeployed airbag as this can cause injury in the event of inadvertent
deployment.

rl Electrical
15.1.6 Fire Hazard Infonnath
Thermal decomposition or combustion may produce dense smoke and other dangerous fumes which in fire situations
form
a highly toxic explosive.
In the event of fire the surrounding area must be evacuated and
all personnel kept well upwind of the area.
Full fire fighting protective gear and
a self contained breathing apparatus operating in the positive pressure mode must
be worn for combating fire. Material near fires must be cooled with water spray to prevent ignition.
Fires should be allowed to burn themselves
out if not threatening to life or property. If fire is threatening to life or prop- erty use copious quantities of water to extinguish.
15.1.7 Ventilath
Local exhaust ventilation designed by a professional engineer should be provided if vapours, fumes, or dusts are gen- erated whilst working with airbag module.
The latest issue of the manual for recommended practices on 'Industrial Ventilation' is available from the
ACGIH Com- mittee on Industrial Ventilation, PO Box 16153, Lansing, MI 48910, USA.
The need for local exhaust ventilation should be evaluated by a professional industrial hygienist.
15.1.8 Respiratory Precauth
To prevent the inhalation of dangerous fumes and dusts, an approved mask should be worn.
15.1.9 Eye Protection
Chemical protective goggles are recommended where there is a possibility of eye contact with the propellant.
Safety glasses with side shields are recommended for
all other operations.
15.1. I0 Protective Clothing
Approved protective gloves, overalls and shoes / boots should be worn.
15.1.1 1 Handling and Storage Precautions
Do not store airbag module near live electrical equipment or circuitry. Store in a dry environment at ambient tempera-
tures.
Good housekeeping and engineering practices should be employed to prevent the generation and accumulation of
dusts. Store in compliance with
all local state and federal regulations.
15.1.12 Driver And Passenger Airbag Modules Assembly / Removal / Service Instructions
Before starting work, ensure ignition switch is in 'IocK position, key is removed and negative terminal cable
is disconnected from the battery.
As the airbag is equipped with a back up power source and due to the risk of airbag being inadvertently
deployed, wait one minute or longer before starting work.
0 Disconnecting the battery cancels the memory for clock, radio, seats, mirrors, steering column and any other
components using battery power. Reset memory after work is completed.
0 Never use airbags from other vehicles, always use new parts.
0 After work is completed, reconnect battery and perform warning light check see diagnostic manual.
0 Never use electrical probes to check voltage or electrical resistance.
0 Disconnect the airbag before carrying out any work on, or in the vicinity of module, or when using electric weld- ing equipment.
0 Always ensure that battery negative has been disconnected for one minute or longer before commencing any
removal procedure.
EB
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