2010 RENAULT SCENIC engine

62A - 7
AIR CONDITIONING
Fault finding - Function architecture62A
V4
Air conditioning system design
The air conditioning system uses four computers. The four computers are connected by the multiplex system, except
in the case of manual air conditioning, where the connection between the air conditioning control panel and the UCH
is by normal wiring.
The air conditioning control panel interprets the driver's wishes and transmits them to the other computers; it also
manages the passenger compartment ventilation, air distribution, air mixing and air recirculation.
The UCH transmits the request to engage the air conditioning compressor to the injection and controls the operation
of the passenger compartment heating resistors (RCH).
The injection receives the refrigerant fluid pressure signal from the pressure sensor. The injection computer
authorises or inhibits the request to engage the compressor depending on how the vehicle is operating and transmits
the signal to the Protection and Switching Unit (UPC).
The role of the UPC is to manage the power section of the air conditioning system. It controls the engagement of the
compressor, the engine cooling fan units and the heated rear screen.
GLOSSARY
RCH = passenger compartment air heating resistors
AC control panelUCH
–interpretation of driver's
wishes
–passenger compartment
ventilation management
–air distribution management
–air mixing management–passenger compartment air
heating resistors operation
management
UPC
(Power and Switching Unit)Injection computer
–engine unit management
–
compressor control
–
heated rear screen control–air conditioning authorisation
Manual air conditioning
and
Climate controlAIR CONDITIONING
Fault finding - Function architecture
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$030.mif

62A - 8
AIR CONDITIONING
Fault finding - Mode of operation62A
V4MR-372-J84-62A000$010.mif
Manual air conditioning
and
Climate controlAIR CONDITIONING
Fault finding - Mode of operation
General operation
The air conditioning system is composed of four sub-functions: heating, cold loop, passenger compartment
ventilation and user selection. Fault finding on the climate control is performed in two different ways using the
diagnostic tool.
The first procedure is by computer fault finding which makes it possible to communicate with just one computer
(select the computer concerned). The second procedure consists of performing fault finding by function which
allows communications to be established with all four computers of the AIR CONDITIONING function.
Description of the subsystems
Heating subsystem: this subsystem includes everything relating to the production of warm air in the vehicle and
management of the heated rear screen.
The main computers involved are the climate control computer (air mixing and blown air setpoint) and the UCH
(control and management of the passenger compartment heating resistors). The Protection and Switching Unit
controls the heated rear screen (and heated door mirror). The injection computer is only included in this subsystem
to supply the signals required for its management.
Cold loop subsystem: this subsystem includes everything involved in the vehicle's production of cold air.
The computers concerned are the climate control computer for air mixing, the injection computer to authorise
compressor engagement and the UPC to control the compressor and the engine fan units. On climate control
systems, the UCH merely transmits the request to engage the compressor from the climate control computer to the
injection computer.
On manual air conditioning systems, the UCH authorises or inhibits transmission of the request to engage the
compressor from the climate control computer to the injection computer depending on the status of the passenger
compartment blower (with manual air conditioning, the UCH receives and manages the passenger compartment
blower speed signal: compressor engagement is inhibited if the fan is not running).
User selection subsystem: this subsystem includes everything used to transmit the user's requests (pressing
buttons). The computers concerned are the climate control computer for climate control systems and the UCH. The
two other computers are not used for manual air conditioning.
Passenger compartment ventilation subsystem (climate control systems only): this subsystem includes
everything involved in ventilation, air mixing, air recirculation and air distribution. Therefore, only the climate control
computer is involved.
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$040.mif

62A - 9
AIR CONDITIONING
Fault finding - Mode of operation62A
V4MR-372-J84-62A000$010.mif
Exchanges between the four air conditioning system computers
–air conditioning request 1 (compressor
engagement)
–switch on passenger compartment heating
resistors (RCH) request
–switch on heated rear screen request
(+ electric door mirrors)
–passenger compartment ventilation signal
Climate
control panelUCH
–passenger compartment heating resistors (RCH)
operation management
–exterior temperature signal
–engine coolant temperature signal
–switch on heated rear screen request
(+ electric door mirrors)
UCHUPC
(Power and Switching Unit)
–alternator charge signal
–number of passenger compartment heating
resistors authorised by alternator
–air conditioning request 2 (compressor
engagement)
–fast idle request for passenger compartment
heating resistors (RCH)
UCHInjection computer
–compressor engagement authorisation
–engine coolant temperature signal
–refrigerant fluid pressure signal
–number of passenger compartment heating
resistors authorised by injection
–compressor engagement request
–switch on engine cooling fan request
Injection computerUPC
(Power and Switching Unit)
–alternator charge signal
Manual air conditioning
and
Climate control
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$040.mif

62A - 13
AIR CONDITIONING
Fault finding - Mode of operation62A
V4MR-372-J84-62A000$010.mif
Summary of components controlled or managed by the UCH
Summary of components controlled or managed by the Protection and Switching Unit
Passenger
compartment
heating
resistors (RCH)
relay No. 2 Passenger
compartment
heating
resistors (RCH)
relay No. 1 Passenger compartment
heating resistors (RCH)
relay No. 3 (Scénic only)Exterior
temperature
sensor
Vehicle
multiplex
network
Actuator control Sensor management
UCH
Air conditioning request
managementHeated rear screen
control
managementPassenger compart-
ment heating resistor
control management
Engine cooling
fan unitHeated rear
screen and
heated door
mirrorsClimate control
compressorAlternator:
"DF"
terminal
Actuator control Electrical availability management
UPC
"DF" terminal signal formatting
(alternator charge)
Key:
Wire connections =
Multiplex connections =
Manual air conditioning
and
Climate control
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$040.mif

62A - 14
AIR CONDITIONING
Fault finding - Mode of operation62A
V4MR-372-J84-62A000$010.mif
Manual air conditioning
and
Climate control
Summary of components controlled or managed by the injection computer
Refrigerant fluid
pressure sensorEngine coolant
temperature
sensorVehicle
multiplex
network
Sensor management
Engine injection computer
Management of the cold loop (refrigerant fluid pressure,
switch on engine cooling fan request, compressor
engagement authorisation, etc.)Passenger compartment
heating resistors (RCH)
authorised power
management
Key:
Wire connections =
Multiplex connections =
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$040.mif

62A - 16
AIR CONDITIONING
Fault finding - Configurations and configuration reading62A
V4
Manual air conditioning
and
Climate controlAIR CONDITIONING
Fault finding - Configurations and configuration reading
Climate control system configurations
Climate control system configuration readings
Computers Configuration Option Comment
Air conditioning (climate
control computers only)CF044 Vehicle type B84/L84/J84/E84 Manual configuration
(with CLIP)
CF117 Type of heating
resistorsWithout/1000 W/
1800 W
UCH SC008 Type of UCH Configuration scenario
(possible to register all the
UCH functions).
Injection (all types)
XXAutomatic computer
configuration
Protection and Switching
UnitCF001 Type of alternator – KCB1 90 BOSCH
–TG11 110 VALEO
–SG12 VALEO
–LIE8 150 BOSCH
–SG15L VALEO
–Other typeManual configuration
(with CLIP)
Computers Configuration reading Option Comment
Climate control LC013 Vehicle type B84/J84/E84 None
LC043 Heating resistor without/1000 W/
1800 W
UCH LC013 Type of air conditioning climate control/
manual/heatingNone
LC030 Type of heating resistorswithout/1000 W/
1500 W
LC011 Vehicle type All except E8h
S3000 injection
NOTE: These
functions are
only valid for the
S3000 injection
(K4J/K4M/F4R
and F4R
Turbocharged
enginesLC009 Air conditioning connected/not
connectedFollowing the first
compressor engagement
request:
LC009 connected
LC016 With LC016 Air conditioning pressure
signal managementwith/without
ET079 Air conditioning present yes/no ET079
LC025 Heating resistor with/without None
Protection and
Switching UnitLC001 Type of alternator – KCB1 90 BOSCH
–TG11 110 VALEO
–SG12 VALEO
–LIE8 150 BOSCH
–SG15L VALEO
–Other typeNone
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$050.mif

62A - 17
AIR CONDITIONING
Fault finding - Conformity check62A
V4
Manual air conditioning
and
Climate controlAIR CONDITIONING
Fault finding - Conformity check
Subsystem: cold loop
NOTESOnly carry out this conformity check after a full check with the diagnostic tool (fault
reading and configuration checks).
Test conditions: ignition on (12
volts APC), engine stopped, AIR CONDITIONING
SWITCHED OFF (passenger compartment blower switched off and air conditioning
compressor not engaged).
NOTE: To check that the temperature parameters are correct (without a thermometer),
read these parameters when the vehicle is cold (in the morning). The temperatures
should be approximately equal (interior, exterior and engine coolant).
Fault finding procedures for the statuses, parameters and commands listed in this
check are explained in the Technical Notes relating to the computer which generates
the signal (see the Introduction section).
Computer
(signal generator)Parameter or status
checked or actionDisplay and Notes Fault finding
Climate controlET143:Air conditioning
request 1.ACTIVE for air conditioning
request (AC button pressed
or AUTO button pressed
with "maximum cold"
request).
INACTIVE otherwise.
NOTE: This status is only
valid for climate control
systems.If there is a fault, refer to the
fault finding procedure
for this status.
NOTE: This status
represents the request from
the climate control
computer to the UCH to
engage the compressor
(refer to the flowchart in
the general operation
section).
PR001:Interior
temperature.X = interior temperature
± 5 ˚C
(invalid value: 87.5 ˚C)If there is a fault, refer to the
fault finding procedure
for this parameter.
ET141:Passenger
compartment
blower.STOPPED
(according to test
conditions: see Notes).If there is a fault, refer to the
fault finding procedure
for this status.
NOTE: This status is only
operative for climate
control systems.
PR012:Mixing flap
position.0% = Max. cold position
(15 ˚C)
100% = Max. warm position
(27 ˚C)If there is a fault, refer to the
fault finding procedure
for this parameter.
PR006:Solar radiation.0 watts (no solar radiation)
to 400 watts (maximum
solar radiation).If there is a fault, refer to the
fault finding procedure
for this parameter.
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$060.mif

62A - 18
AIR CONDITIONING
Fault finding - Conformity check62A
V4
Manual air conditioning
and
Climate control
Subsystem: cold loop (continued 1)
Computer
(signal generator)Parameter or status
checked or actionDisplay and Notes Fault finding
UCHET030:Air conditioning
request 2.INACTIVE
(engagement of the
compressor is only
authorised when the engine
is running).If there is a fault, refer to the
fault finding procedure
for this status.
NOTE: This status
represents the request from
the UCH to the injection
computer to engage the
compressor (refer to the
flowchart in the general
operation section).
PR002:Exterior
temperature.X = exterior temperature
± 5 ˚C
(invalid value: 215 ˚C)If there is a fault, refer to the
fault finding procedure
for this parameter.
ET015:Passenger
compartment
blower.INACTIVE
(according to test
conditions: see Notes).If there is a fault, refer to the
fault finding procedure
for this status.
NOTE: This status is only
operative for manual air
conditioning (and heating
versions without air
conditioning).
ET091:Engine running.NO
NOTE: This status is
displayed by the UCH but it
is generated by the injection
computer.If there is a fault, refer to the
fault finding procedure
for this status.
(Injection Technical Note).
InjectionET079:Air conditioning
present.YES
(automatic injection
computer configuration).If the status displays NO,
refer to the fault finding
procedure for this status.
PR064:Coolant
temperature.X = engine coolant
temperature.If there is a fault, refer to the
fault finding procedure
for this parameter.
ET004:Air conditioning
authorisation.NO
(no authorisation with
engine stopped).If there is a fault, refer to the
fault finding procedure
for this status.
CLIM X84 1.1
Edition 2
MR-372-J84-62A000$060.mif