engine coolant RENAULT SCENIC 2009 J84 / 2.G Air Conditioning Climate Control Workshop Manual

62B - 7
CLIMATE CONTROL
Fault finding – System operation62B
V3 MR-372-J84-62B000$020.mif
Vdiag No.: 44
CLIMATE CONTROL
Fault finding – System operation
GENERAL INFORMATION:
The climate control system fitted on the SCENIC is controlled by four computers. This system is called a
DISTRIBUTED FUNCTION. Fault finding on the climate control is performed in two different ways using the
diagnostic tool. The first method consists of performing fault finding on each computer which allows
communications to be established with just one computer (select the climate control computer). The second
procedure consists of performing fault finding on each function which allows communications to be established
with all four computers of the AIR CONDITIONING function. These two fault finding methods are described in the
introduction of this repair manual.
DESCRIPTION OF THE OPERA
TION OF THE CLIMATE CONTROL COMPUTER:
The climate control computer controls the passenger compartment ventilation, the distribution motor, the mixing
motor and the recirculation motor.
The climate control computer also controls two sensors, these being the interior temperature sensor and the solar
radiation sensor.
The two sensors and the three motors are connected to the climate control computer by wire connections. The
climate control computer controls the passenger compartment ventilation using a modulated control signal (square
signal) sent to a power module (wire connection).
All other signals used by the climate control computer or transmitted by this computer to other computers are sent on
the multiplex network.
Cold air production (cold loop) and warm air production (heating) are controlled by the other three computers
involved in the Air conditioning function (UCH, protection and switching unit and injection computer).
The main signals used by the climate control computer are:
–+ 12 V sidelights,
–0 V rheostat controlled,
–exterior temperature,
–engine coolant temperature,
–engine operating status,
–engine speed,
–electrical power consumed,
–request to set the blown air temperature.
OPERA
TING NOTES:
–When the engine is switched off, the passenger compartment blower unit operates approximately 30% slower than
the requested speed (control panel setting).
–If any of the actuators are faulty, the air conditioning can no longer control them, but the setting requests are still
displayed on the control panel: warning lights light up, display of symbols on the control panel (distribution motor
position, passenger compartment blower speed, AC symbol, etc.).
–If the exterior 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 exterior
temperature sensor by the UCH).
ACREG X84 1.1
Edition 2
MR-372-J84-62B000$020.mif

62B - 28
CLIMATE CONTROL
Fault finding – Interpretation of parameters62B
V3 MR-372-J84-62B000$080.mif
Vdiag No.: 44
CLIMATE CONTROL
Fault finding – Interpretation of parameters
PR001
INTERIOR TEMPERATURE
NOTESNone.
The climate control computer receives the interior temperature signal through a wire connection.
To ensure this parameter is correct (without using a thermometer), simply read the temperature information
when the vehicle is cold (in the morning). The interior temperature, the exterior temperature and the engine
coolant temperature should be practically the same.
Another way of checking whether this sensor is correct is to check the resistance value of the sensor according
to temperature: refer to the electrical specifications of the sensor in the Help section.
If the temperature displayed by this parameter seems to be incorrect, apply the fault finding procedure for fault:
DF007 Interior temperature sensor circuit.
AFTER REPAIRRepeat the conformity check from the start.
ACREG X84 1.1
Edition 2
MR-372-J84-62B000$080.mif

62B - 34
CLIMATE CONTROL
Fault finding – Interpretation of parameters62B
V3 MR-372-J84-62B000$080.mif
Vdiag No.: 44
PR121
BLOWN AIR TEMPERATURE SETTING
NOTESNone.
This parameter is used to control the temperature inside the passenger compartment. This setting is calculated
by the climate control computer according to interior temperature, exterior temperature and coolant
temperature.
This setting is used to control the mixing motor and the request to operate the passenger compartment air
heating resistors (to reach the temperature requested by the user as quickly as possible in order to optimise
passenger compartment comfort quickly).
The following conditions must be satisfied to allow the UCH to control the passenger compartment air heating
resistors:
–Engine running,
–Passenger compartment blower running (minimum speed 1),
–User temperature setting above 20 ˚C (or automatic mode requested),
–Blown air temperature setting above 65 ˚C,
–Interior temperature below 10 ˚C,
–Exterior temperature below 5 ˚C,
–Engine coolant temperature below 65 ˚C,
–Injection authorisation (ET019 Number of RCHs authorised by injection system < at 1),
–Alternator authorisation (ET018 Number of RCHs authorised by alternator < at 1).
Note:
–Statuses ET017, ET018 and ET019 are indicated by the UCH (see conformity check of air conditioning
function: Section 62A).
–The values given below are average values. The UCH calculates the number of passenger compartment
heating resistors to trigger (ET017 number of RCH required).
AFTER REPAIRRepeat the conformity check from the start.
ACREG X84 1.1
Edition 2

62B - 35
CLIMATE CONTROL
Fault finding – Conformity check62B
V3 MR-372-J84-62B000$090.mif
Vdiag No.: 44
CLIMATE CONTROL
Fault finding – Conformity check
PASSENGER COMPARTMENT VENTILATION SUB-FUNCTION
NOTESOnly carry out this conformity check after a full check with the diagnostic tool (fault
reading and configuration checks).
Test conditions: engine off, ignition on (forced 12 V After ignition).
Air conditioning off
(air conditioning compressor not triggered).
Special note:
The various conformity checks
for the air conditioning function are explained in the
Introduction section.
Note:
–Read the parameters when the vehicle is cold (in the morning) to check the
conformity of the temperature parameters (without thermometer). The two
temperatures should be practically the same (as should the coolant temperature
given by the injection system).
–The invalid values given in this check correspond to the value sent by the diagnostic
tool (substitute value) when the sensor in question is faulty. A sensor fault can be
detected when these invalid values are displayed (this is an important point for
sensors on which fault finding cannot be performed, e.g. exterior temperature
sensor).
Order FunctionParameter or Status
checked or Action Display and Notes Fault finding
1TemperaturesPR001:Interior
temperatureX = interior
temperature ± 5 ˚C
(invalid value: 87.5 ˚C)If there is a fault, refer to the
fault finding procedure
for this parameter.
PR002:Exterior
temperatureX = exterior
temperature ± 5 ˚C
(invalid value: 215 ˚C)
Note: This status is
reset by the climate
control computer but
its source is the UCH.In the event of a fault, refer
to the interpretation of this
parameter (see
Section 87B).
2Solar radiationPR006:Solar radiationfrom 0 W
(no solar radiation) to
400 W
(maximum solar
radiation)
(invalid value:
765 W)In the event of a fault, see
the interpretation of this
parameter.
ACREG X84 1.1
Edition 2
MR-372-J84-62B000$090.mif

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

62B-49
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 4
CONTINUED
Is it an air flow fault?
NO
Is it a heater performance fault?
NO
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).
Is the fault still present?
YES
Carry out a conformity check of the temperature sensors
(internal, external and engine coolant temperature).
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.YES
YESSee ALP 3.
See ALP 6.
NO
End of fault finding procedure.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2

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