
Climate Control Systems 
System Differences 
m: 
Heater only vehicles  do not  have  the following fitted: 
This section applies generally  to both  air conditioning  and heater systems.  System specific descriptions, pro- 
cedures, tests etc. are indicated. 
0 Solar  sensor 
0 Clutch request  and acknowledge  circuitry. 
0 Refrigerant  pressure switch. 
0 Control panel - deletion of air  conditioning  button. 
6 cyl. engined vehicles  do not have either  the electrical  load inhibit or the  compressor lock  sensor. 
Heated Front Screen 
(HFS) is  optional  on both  air conditioning  and heater  panel versions. 
14.2  COMPONENT  DESCRIPTIONS 
14.2.1  Control  Panel 
The control  panel (Fig. 1) provides the operator interface  with the climate  control system. 
The  control  panel communicates  with the 
A / CCM via a serial data  communications  link.  During each data  transfer 
cycle  the control  panel states  whether it is an  air conditioning  or heater version,  thus enabling  the A/ CCM to control 
the  system  functions  accordingly. 
Tontrol panel operation is  described in detail in the  'Climate  Control Systems'  section of the  VSM. 
- 
Fig. 1 Control  Panel (A / C with Heated  front Screen) 
J86 - I726 
14.2.2  Control  Panel Inputs /Outputs 
Description I CableColor 
I 1 I Output clock I Grey I 
2 Output start  Grey / Red 
3 Input data 
in  Grey / Yellow 
4 Output 
data out  Grey / Green 
5 Output 
ignition  positive  White / Red 
6 Output auxiliary positive 
White / Blue 
7 Output 
ground  Black 
8 Dimmer 
Red 
9 Dimmer override Red / Green 
I 10 I Not connected I- I 
I 11 I Not connected I- I 
I 12 I Not connected l- I 
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Climate Control Systems 
14.2.16  Servo Motor  Control 
The system incorporates  several servo motors  which direct the flow of  air through the  air conditioning  system. The 
motors  are driven  by A / CCM signals  in either a clockwise or anti-clockwise direction. 
Servo  motor  position  is monitored  via 
a feedback potentiometer situated  within the motor housing. 
The  system  servos comprise: 
o RH and LH Air  intake servos (Fresh / Recirc.). 
0 Centre  vent servo. 
o Defrost (screen  vent) servo. 
0 Footservo. 
0 Cool air by-pass  servo. 
14.2.17  Blower Motor Control 
The A/ CCM controls  two blower  motors,  delivering  airflow 
to  the  evaporator / heater unit, at variable  fan speeds.  The 
blower motors  are regulated  by power transistor  modules 
which  provide linear  variation of blower  speed; the blower 
speed 
is increased  or reduced  progressively in response  to 
vehicle  speed, minimising  the ram  effect  of forward  motion. 
The  blower motors  are inhibited when  engine coolant tem
- perature is below 30°C and  heating  is requested. 
14.2.18  Differential Control 
The differential  control is mounted  on the  facia  centre  vent. It is used  to control  the temperature  difference between the 
upper and lower  outlets.  Fig. 
1 Servo 
Motor 
14.2.19  Heated Rear Window,  Door Mirrors  and Front  Screen 
The Heated  Rear Window (HRW) function  can only  be activated  with the ignition  on and  the engine running.  Operation of the HRW  switch  operates  the status  condition  LED on the  control  panel and switches  on the HRWfor approximately 21 minutes.  Selection  of the  HRW  also operates  the door mirror heaters  for approximately 11 minutes.  The operation 
can  be cancelled  by switch  re-selection  or ignition off. System off does  not cancel  the HRW  operation. 
The Heated Front Screen 
(HFS) function  can only  be activated  with the ignition  on and  the engine  running,  and either 
‘defrost’  mode selected  or HFS  selected.  Each half, left and right hand  split, switches  on for approx. 6.5 minutes.  The 
operation  can be cancelled  by switch  re-selection  or ignition off. System off does  not cancel  the HFS  operation. 
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Climate Control Systems 
Actlon 
Simultaneously hold FACE and FAN  and switch the ignition 
ON 
14.4 CLIMATE  CONTROL  SYSTEM TEST 
The control  panel has a self-diagnosis  feature, and is capable  of displaying  and deleting  stored fault codes. 
Climate  control is an  integrated  system, therefore 
it is recommended  that the Portable Diagnostic  Unit (PDU) is used 
for  fault  diagnosis.  The  fault codes  displayed  with the control  panel self-diagnosis feature  are not  as comprehensive 
as  those  of the  PDU.  The PDU  will display  the relevant fault  code, fault code  description and  information of the  system 
peripherals  at the  time  the fault  occurred. 
Resu It 
Control panel inputs  for clock,  start, data,  ignition  +ve and 
auxiliary  +ve are simultaneously examined  and cause indi- 
cator LED’s to illuminate  on satisfactory  line test. 
14.4.1 
System error  information is stored  in the  A/ C CM up to a maximum  of 5 faults. Should  a fault  occur  there will be an 
audible’beep‘and  the message ‘Er’will be displayed  on thecontrol  panel LCD display  for some 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 
following  procedure.  A  list and description  of all  accessible  fault codes  is provided  on the  following  page. 
Fault Code Extraction and  Deletion Procedure 
I Item Check LED 
Ignition  Defrost 
Auxiliary  Face 
Clock  Feet 
/ face 
Start  input  Foot 
Data  out  Screen 
/ foot 
Dimmer  override  Recirc. 
. Switch off the ignition. 
Press  and hold  the ‘Auto’  and ‘Fresh / Recirc.’  buttons  simultaneously,  and switch  on the  ignition. 
. All the  control  panel LED’s and all LCD  segments  will flash  on and off. Any  function  LED indicator  which does not 
flash  on / off suggests a fault condition  within that area  of the  panel  or, with  the LED. 
Any  LCD  element  which fails to flash  on 
/ off indicates  a fault  within  the panel  or display  element. 
. Press ‘Auto’. 
. Press ‘Face‘  to scroll  through  a maximum  of 5 fault codes. 
W 
Thecontrol  panel display  will flash  repeatedly  indicating a list oftwo digit  numbers (refer  to following  page for code 
analysis). 
. If, when  a code  is displayed,  an accompanying  ‘beep‘ is emitted,  the indicated  fault is current and therefore still pres- ent  within the  system.  A  code displayed  without an accompanying  ‘beep’ indicates a  fault had previously occurred 
but  is not  present  within the system. 
It is advisable  to check  all areas  indicated with cleared  fault codes.  Such faults may re-occur if intermittent 
problems  are present in the system. 
If 
’0‘ is 
displayed,  there are no stored  fault codes,  wait 30 seconds  to allow  system  self-test. 
W: 
. To delete  stored  and cleared  fault codes  simultaneously  press ‘HRW and ‘FACE‘  switches. 
. After investigating  and correcting  all stored  faults,  press  the ‘Push Off button  to restore  normal operation with de- 
fault panel  settings, ie AUTO  at 24OC. 
Condition 
IGN input  at 12V, check  LED is illuminated 
AUX 
input at 12V, check  LED is illuminated 
Clock 
input normal,  check  LED is illuminated 
Start  input  normal,  check LED is illuminated 
Data  out input  normal,  check  LED is illuminated 
Dimmer  override  input 
ON, check LED is illuminated 
14.4.2 Panel  Communications Check 
Panel communications  check verifies  the inputs  and outputs  from the control  panel to the  A/ CCM. 
To  exit  the panel  communications  check mode press the system  ON button. 
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Climate Control Systems 
Position Action Value Test point 
Closed  Face 1 k2 
Open  Foot 
4k8 
Closed  Face 
4k8 
Open  Foot 
1 k2 
Pin  2 ground 
Pin 
9 +5 volts 
14.7.15 Fault  Code  36 
Foot  Vent 
Potentiometer 
Disconnect  the COOL  AIR BYPASS  yellow, Sway connector. 
. Test the 5V supply  to the potentiometer at the main  unit, pin 9 (positive)  and pin 2 (ground). 
If there is  no 5 volt supply,  inspect the harness  for open  circuit or short circuit  to ground. If no  harness  faults are appar- ent, renew  the A I CCM. 
&&: The A I CCM provides a common 5V output  and ground  to all servos, ie all servo potentiometers  are fed by a 5V rail. If all servos are inoperable  check the A 1 CCM outputs  and harness,  renew the A 1 CCM. 
Check  resistance between  potentiometer connector pins9 and 
2 at blower  motor connector,  value should  be 6kn +10% 
at 20°C. 
Measure  the resistance  from the potentiometer wiper  (pin 
6) to pins 9 and 2 respectively.  Resistances should read: 
14.7.16  Fault Code  4 1 
1 H Fresh / Recirc.  Motor 
The resistance between  pins 1 and 3, servo unit Sway connector,  should read 4.8 - 7.2 kn. 
If the  resistance is  outside of the  set limits,  renew  the servo  unit. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor %way connector,  and ground  to pin 4 of the  connector.  The  motor arm should rotate smoothly  in a clockwise direction.  Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, servo  unit %ay connector,  and ground  to pin 5. The  motor  arm should rotate smoothly 
in a anti-clockwise  direction.  Renew the motor if the arm  does not rotate  smoothly. 
Inspect  the harness  for open  circuit or short circuit  to ground.  Rectify as necessary. 
If no  harness  faults are apparent, 
renew  the AI CCM. 
14.7.17  Fault Code  42 
RH Fresh / Recirc.  Motor 
The resistance  between pins 1 and 3, servo unit Sway connector,  should read 4.8 - 7.2 kn. 
If the resistance  is outside  of the set limits,  renew  the servo  unit. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor Sway connector,  and ground  to pin 4 of the  connector.  The  motor arm should rotate smoothly  in a clockwise  direction.  Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, servo  unit Sway connector,  and ground  to pin 5. The  motor  arm should rotate smoothly 
in a anti-clockwise  direction. Renew the motor if the arm  does not rotate  smoothly. 
Inspect  the harness  for open  circuit or short circuit  to ground.  Rectify as necessary. 
If no  harness  faults are apparent, 
renew  the A I CCM. 
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Climate Control Systems 
14.7.18  Fault Code  43 
Cool  Air Bypass  Servomotor 
The resistance between  pins 1 and 3, motor Sway connector,  should read 4.8 - 7.2 WZ. 
If the resistance  is outside of  the set limits, renew the  motor. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor Sway connector,  and ground  to pin 
4 of the  connector.  The  motor arm should rotate smoothly  in a clockwise  direction.  Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, motor Sway connector, and  ground to pin 5. The  motor  arm should rotate smoothly 
in a anti-clockwise  direction.  Renew the motor if the arm  does  not rotate smoothly. 
Inspect  the harness  for open  circuit or short circuit  to ground.  Rectify as necessary. 
If no  harness  faults are apparent, 
renew  the AI CCM. 
14.7.19  Fault Code  44 
Servomotor 
- Defrost 
The resistance  between pins 1 and 3, motor  Sway  connector,  should read 4.8 - 7.2 kQ. 
If the resistance  is outside of  the set limits,  renew the motor. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor Sway connector, and ground  to pin 4 of the  connector.  The motor arm should rotate smoothly  in a clockwise direction. Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, motor Sway connector,  and ground  to pin 5. The  motor  arm should rotate smoothly 
in a anti-clockwise direction.  Renew the motor if the arm  does  not rotate smoothly. 
inspect  the harness  for open  circuit or short circuit  to ground.  Rectify as necessary. 
If no  harness  faults are apparent, 
renew the A I CCM. 
14.7.20  Fault Code  45 
Servomotor 
- Face 
The resistance  between pins 1 and 3, motor &way connector,  should read 4.8 - 7.2 WZ. 
If the resistance  is outside of  the set limits, renew the  motor. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor Sway connector,  and ground  to pin 4 of the  connector.  The  motor arm should rotate smoothly  in a clockwise direction.  Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, motor 5-way connector, and  ground to pin 5. The  motor  arm should rotate smoothly 
in a anti-clockwise  direction.  Renew the motor if the arm  does not rotate smoothly. 
Inspect  the harness  for open  circuit or short circuit  to ground.  Rectify  as necessary. 
If no  harness  faults are apparent, 
renew  the AI CCM. 
14.7.21  Fault Code  46 
Servomotor 
- Foot 
The  resistance between  pins 1 and 3, motor Sway connector, should read 4.8 - 7.2 WZ. 
If the resistance  is outside of  the set limits, renew  the motor. 
The  motor  operation  can be checked  by applying battery voltage  to pin 
5, motor Sway connector,  and ground  to pin 4 of the  connector.  The  motor arm should rotate smoothly  in a clockwise direction.  Renew the motor if the arm  does 
not rotate  smoothly. 
Apply battery voltage  to pin 
4, motor Sway connector, and  ground to pin 5. The  motor  arm should  rotate smoothly 
in a anti-clockwise  direction.  Renew the motor if the arm  does not rotate  smoothly. 
Inspect  the harness  for open  circuit or short circuit  to ground.  Rectify as necessary. 
If no  harness  faults are apparent, 
renew  the AI CCM. 
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rl Electrical 
FAULT CODE 32 
Driver-side Air Bag  Circuit  High Resistance  or Open 
Normal Operation 
The  DM monitors  the resistance  between pins 10 and 11. The value  of this  resistance  is the sum  of the  two  cable reel 
cassettes,  the air bag and  is normally  between 
1.5~2 and 2Q. If the resistance  measured exceeds 4Q the MIL  Lamp will illuminate  and fault code 32 will be present,  indicating high resistance  or open  circuit  on the  air bag  circuit. 
Possible  Causes 
0 Poor connections  or corrosion at clockspring / main  harness connections. 
0 Open  circuit  or high  resistance  of cable reel  cassettes. 
0 Open circuit  or high  resistance in driver-side air bag. 
0 Faulty driver-side  air bag wiring. 
Fault  Diagnosis 
1. Circuit - check 
. Disarm SRS system and  disconnect DM. 
Disconnect  DM and  remove  plastic locking wedge  from black  DM harness  connector. 
. Measure  resistance  across harness  connections  to passenger  air bag,  wires KN and RF! 
. Is resistance  value less than 2Q ? 
Yes - 
. Ensure  locking  wedge has been  removed  correctly from black  connector. 
. Examine  harness for broken, dirty or incorrectly  seated connections. 
. Rectify  faults as necessary. 
No - Proceed  to step 2. 
2. Resistance -check 
. Is resistance  measured in step 1 greater  than 352 7 
Yes - Proceed  to step 4. 
No - Proceed  to step 3. 
3. Fault  code verification 
. Reconnect  DM and  check if code 32 is still present. 
Yes 
- Renew DM. 
No - Examine  harness or broken, dirty or  incorrectly  seated connections.  Rectify  faults as necessary. 
4. Resistance -check 
. Disconnect cable  reel cassette  at base  of steering column. 
Install  air bag simulator  (ensure 2Q resistance of simulator  before connection) in place of cable reel cassette. 
Measure resistance  across harness connections  to air  bag,  wires KIN and RI? 
Is resistance  equal to between 1.m and 2.2Q 7 
Yes - Renew cable  reel cassette. 
No - Examine  harness wiring for open  circuit,  rectify faults  as necessary. 
5.  On completion. 
. Arm  and verify the SRS system. 
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