Page 41 of 60
62B-41
CLIMATE CONTROL
Fault finding – Customer complaints62B
V3 MR-372-J84-62B000$100.mif
Vdiag No.: 44
CLIMATE CONTROL
Fault finding – Customer complaints
NOTESSpecial notes:
A general summary of all air conditioning fault finding charts can be found in
Section 62A. The customer complaints listed below only relate to the actuators
controlled by the air conditioning control panel. For cold air and warm air production
faults, refer to Section 62A.
DIALOGUE FAULT
NO DIALOGUE WITH THE COMPUTER ALP 1
AIR DISTRIBUTION PROBLEM
AIR DISTRIBUTION PROBLEM ALP 2
AIR FLOW FAULT ALP 3
INEFFICIENT WINDSCREEN DEMISTING ALP 4
NO PASSENGER COMPARTMENT VENTILATION ALP 5
PASSENGER COMPARTMENT
ODOURS
UNPLEASANT ODOURS IN PASSENGER COMPARTMENT ALP 11
WATER IN PASSENGER COMPARTMENT
WATER IS PRESENT IN PASSENGER COMPARTMENT ALP 12
CONTROL PANEL FAULT
NO CONTROL PANEL LIGHTING ALP 13
ACREG X84 1.1
Edition 2
Page 42 of 60
62B-42
CLIMATE CONTROL
Fault finding – Customer complaints62B
V3 MR-372-J84-62B000$100.mif
Vdiag No.: 44
NOTESSpecial notes:
A general summary of all air conditioning fault finding charts can be found in
Section 62A. The customer complaints listed below only relate to the actuators
controlled by the air conditioning control panel. For cold air and warm air production
faults, refer to Section 62A.
COMPRESSOR NOISES
AIR CONDITIONING NOISES DURING OPERATION ALP 14
PASSENGER COMPARTMENT VENTILATION NOISES ALP 15
Edition 2
Page 46 of 60

62B-46
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 3 Air flow fault
NOTESOnly consult this customer complaint after a complete check using the diagnostic
tool.
Check that the customer knows how to work the air conditioning system properly.
Is the passenger compartment fan working?
YES
Check that the air circuit (cabin filter, scuttle panel grille, air ducts and ventilation grilles, etc.) is not blocked.
Ensure that the blower blades are in good condition.
Repair, clean or change the cabin filter if necessary.
With the cabin filter removed, put your
hand into the housing to ensure that the
evaporator is not obstructed and that
there is no ice.
Is the evaporator obstructed?
NO
Ensure that the blower unit is properly sealed. Also check that the air distribution ducts (right-hand and left-hand,
upper and lower) are correctly connected to the housing as well as the refrigeration pipe in the glove box (if the
customer complains about a feeling of cold air on the passenger's side).
Repair if necessary.
Check that the air recirculation flap does not remain closed when in the recirculation position. On the diagnostic
tool, status ET062 "Recirculation flap position" should display OPEN (the flap can be seen by removing the
windscreen frame).
Repair if necessary (apply the fault finding procedure for fault DF021 Recirculation motor circuit).
Does the fault disappear when the air distribution is
changed?
NO
NO
YES
YESRepair, see ALP 5
Remove the evaporator and clean if it is obstructed.
If there is ice on the evaporator, carry out a conformity
check of the temperature sensors (internal, external
and engine coolant temperatures). Depending on
vehicle equipment, check that the interior air
temperature sensor micro-turbine is working correctly
(if it is faulty it may cause the measurement to be
incorrect).
Replace any faulty components.
Ensure that all the air vents
are open.
If the fault is still present,
see ALP 2.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 48 of 60

62B-48
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 4 Inefficient windscreen demisting
NOTESOnly consult this customer complaint after a complete check using the diagnostic
tool.
Special notes:
Check that the inside of the windows are not greasy, as this lowers the efficiency
of the demister.
Check that the air extraction vents are not blocked.
Repair if necessary.
Is the fault still present?
YES
Ensure that there are no water leaks into the passenger
compartment which would significantly increase the humidity
and reduce the effectiveness of the demisting.
Repair if necessary (see ALP 12).
Is the fault still present?
YES
Check that the compressor is operating correctly by running command: AC008 Compressor command
(Protection and Switching Unit command mode) or by operating the air conditioning (press AC button).
Repair if necessary (see ALP 8 No cold air, in section 62A).
Check that the condensation drain ring (water from the evaporator) is not obstructed (underneath the body).
Repair if necessary.
Is it an air distribution fault?
NO
NO
NO
YESEnd of fault finding procedure.
End of fault finding procedure.
See ALP 2.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 50 of 60

62B-50
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 5 No passenger compartment ventilation
NOTESOnly consult this customer complaint after a complete check using the
diagnostic tool.
Special notes:
The 2 x 5-track intermediate connector is located on the LH side of the distribution /
ventilation unit (behind a plastic cover) and the passenger compartment fan control
module is located slightly higher up, below the heater matrix pipes.
Check that the fusesare in good condition.
Using the diagnostic tool, check that the passenger compartment fan
control setting given by the computer varies from 0 to 100% by checking
parameter PR019 Passenger compartment fan PWM setpoint
(refer to the interpretation of this status).
Does the value vary?
YES
Check that the control voltage (PWM) (modulated control voltage) of the passenger
compartment fan power module varies between 5 and 12 V (from 0 to 100%) by
measuring between track 6 of the module's 6-track connector and earth
(connector connected).
Note:
The check procedure is given in the Help section.
Does the voltage vary correctly?
NO
Check the insulation, continuity and absence of interference resistance on the
following connection:
Air conditioning computer 18-track
connector
track 7
Repair if necessary.Power module 6-track connectortrack 6
With the ignition on, check for +12 V accessories feed on track B1 and an earth on track B5
of the black 2 x 5 track intermediate connector (screwed to the base of the console).
Repair if necessary.
NO
YES Contact your
TECHLINE.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 52 of 60

62B-52
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 11 Unpleasant odours in the passenger compartment
NOTESOnly consult this customer complaint after a complete check using the
diagnostic tool.
Check that the cabin filter is not blocked or damaged.
Replace it if necessary.
Is the fault still present?
YES
Check that the condensation drain ring (water from the
evaporator) is not obstructed (under the body).
Repair if necessary.
Is the fault still present?
YES
Check the sealing of the heating unit in relation to the engine
compartment:
–Foam seal on the heater matrix coolant pipes fitted and in
good condition.
–Rubber seal on the radiator tank fitted and in good condition
(seal under the bonnet separating the engine compartment
from the windscreen aperture).
–Drain valve on the radiator tank fitted and in good condition.
Repair if necessary.
Is the fault still present?
YES
Remove the cabin filter to apply air conditioning system
cleaner using an extension pipe on the evaporator.
Spray the entire contents of the aerosol.
Leave the product to work for 15 minutes.
NO
NO
NOEnd of fault finding procedure.
End of fault finding procedure.
End of fault finding procedure.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 54 of 60

62B-54
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 13 No control panel lighting
NOTESOnly refer to this customer complaint after a full check of the multiplex network
and the air conditioning with the fault finding tool.
Special notes:
With the ignition on, the control panel screen is permanently on but the panel buttons
only light up when the sidelights are switched on.
Note:
If the external temperature sensor is faulty, the climate control computer is
switched on 5 seconds after the ignition is switched on (this allows a fault to be
identified as fault finding cannot be performed on the external temperature sensor
by the UCH).
Is the fault common to other components (instrument panel,
multifunction display, electric window buttons, etc.)?
YES
Switch on the ignition and switch on the side lights to check
there is a 12 V supply on track 6 of the brown 12-track
connector (PPH2) of the Protection and Switching Unit.
Is there a 12 V supply?
YES
Check the connection and the condition of the connectors at the air conditioning control panel
output.
Repair if necessary.
Check the insulation, continuity and absence of interference resistance on the following
connection:
Air conditioning computer 12-track connector
track 9
Repair if necessary.Protection and Switching Unit brown 12-track
(PPH2) connector
track 6
NO
NOPerform fault finding on the
protection and switching unit.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 55 of 60
62B-55
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 13
CONTINUED
Using the diagnostic tool and the conformity
check in this document, check that the lighting
rheostat is working correctly using parameter
PR122 Night-time lighting level.
Does the parameter vary?
YES
Is the fault still present?
YES
Contact your TECHLINE.
NO
NO Use the diagnostic tool to check the
instrument panel (which is providing the 0 V
rheostat controlled information).
If fault DF037 "Instrument panel lighting
rheostat" is present: apply the associated fault
finding procedure (see corresponding
section).
If no faults are present or stored: run fault
finding on the multiplex network (the 0 V
rheostat controlled signal is reaching the air
conditioning control panel on the multiplex
network).
End of fault finding procedure.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2