2008 RENAULT SCENIC engine

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-11
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-11V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
f/ Display:
Unlocking is indicated by 1 flash of the direction indicators.
Locking is indicated by 2 flashes of the direction indicators.
When using the "boot status toggle" switch, display is not performed if a toggle request is made when the vehicle is
completely unlocked. In fact, in this case, the vehicle is not locked as only the boot is locked.
If one of the opening elements is detected as open when the request for locking the vehicle is made, the UCH will not
authorise vehicle locking and no indicators will flash to warn the user.
1.1.2 procedure of locking/unlocking by pressing the central door locking button:
This button is used to lock/unlock the vehicle while stationary or moving.
This button has no effect if the vehicle has been locked using the card in hands-free or manual mode.
Pressing the electric central door locking button when a door is unlocked will lock all the doors and the electric
central door locking indicator light will light up. Status ET044 CPE* button may be used to check that the button is
operating correctly.
The operation of the electric central door locking indicator light can be checked using command mode AC020 CPE*
button indicator light.
1.1.3 Principle of automatic locking when driving (RAID* system):
The Automatic Locking when Driving (RAID) function locks the vehicle as soon as the speed signal is above
approximately 4 mph (7 km/h).
Activation or deactivation of the RAID function can be viewed using ET043 RAID* function authorisation by CPE*.
The RAID function can be activated or deactivated by pressing and holding the electric door locking button for
approximately 5 seconds while the engine is running. Acknowledgement is indicated by a buzzer.
1.1.4 Principle of automatic relocking:
Automatic relocking takes place 2 minutes after hands-free or card unlocking if unlocking is not followed by the
opening of a door.
CPE*: Electric central door locking
RAID*: Renault Anti-Intruder Device Note:
Unlocking can be performed by the UCH if the airbag computer has detected an impact or if it is faulty (not
recognised on the multiplex network, internal fault, etc.). (see 88B, Multiplexing).

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-26
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-26V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
b/ Locking the steering column:
The steering column is locked with the engine off, after the Renault card is removed from the card reader. This
locking operation requires:
–a valid 0 mph (0 km/h) speed signal,
–a correctly functioning airbag and no impact detected,
–a deactivated + after ignition connection.
When the engine has not been started but the after ignition feed is active (e.g. forced after ignition feed), certain
conditions in which there is a drop in the after ignition feed do not cause the steering column to lock ("steering
column not locked" message).
Steering column lock fails if:
1/ Normal non-locking scenarios:
–the card is present in the card reader,
–more than 20 minutes has elapsed with the card in the reader and the engine off,
–the vehicle speed is not zero,
–power is demanded by the steering column lock too frequently.
With regard to vehicles fitted with UCH computer Vdiag 4F or above:
–the Renault card is removed from the card reader when the vehicle is in forced + after ignition feed,
–3 minutes have elapsed following a starting failure due to an engaged gear,
–the Renault card is removed from the card reader following a starting failure due to an engaged gear,
–a front door is open following a starting failure due to an engaged gear and the card is not in the reader.
To lock the steering column, start and stop the engine again.
2/ Abnormal non-locking scenarios:
–the airbag unit is faulty or locked,
–the airbag unit is disconnected,
–the airbag has been triggered,
–the speed signal is not available.
In the event that a steering column does not lock, the driver is informed via the message Steering column not locked.
1.2.3 Locking the injection computer:
When the + after ignition feed has been established, the UCH and the injection computer compare their codes via
the multiplex network. If the codes are identical, the vehicle immobiliser is deactivated (ET046 Immobiliser).
If there is a failure, the immobiliser remains active.
Reactivating protection: the immobiliser is reactivated when the engine stops.

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-27
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-27V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.2.4 Renault card check by the UCH:
a/ Card check:
When the engine is running, the UCH checks for the presence of the Renault card in the passenger compartment (if
vehicle is hands-free) or in the card-reader when a door is opened then closed. If the Renault card is not detected, a
message on the instrument panel and a buzzer warn the driver.
Command AC036 Internal aerial test is used to check the area covered by the starting aerials inside the passenger
compartment (hands-free vehicles). The card reader flashes when the card is detected.
This command allows a hands-free card to be recognised even if it does not belong to the vehicle.
b/ Low battery warning:
If the Renault card battery is faulty or flat, the change card battery message is displayed on the instrument panel
when the vehicle is started, if there have been 5 attempts to authenticate the Renault card since the battery fault.
c/ Storing information on the card:
A device allowing information relating to the vehicle to be read from the card is available.
Information available: – VIN (Vehicle Identification Number).
–Mileage.
–Fuel level.
–Mileage before oil change.
–Tyre pressure (if vehicle fitted with SSPP).
–Status of OBD warning light.
–Oil level.
2.5 Immobiliser warning light programs
Immobiliser warning light Vehicle protection status
Ignition
offWarning light flashes slowlyVehicle protected (immobiliser active or fault with
steering lock)
Warning light not lit New vehicle or blank UCH storage mode
Ignition
onWarning light flashes slowly Renault card not recognised
Warning light continuously lit Injection authentication fault
Warning light not lit Vehicle unprotected (immobiliser inactive)

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-28
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-28V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.3 SUB-FUNCTION: STARTING
The UCH manages the control section of the starting sub-function. For this function to operate normally, the
protection function must proceed correctly (immobiliser inactive ET046 Immobiliser).
In order to control the starter motor, the UCH requires the following status and parameter information to check that
the starting conditions have been met:
–Start button ET070 Start button.
–Clutch pedal position ET048 Clutch pedal position.
–Brake pedal position ET047 Brake pedal position.
–Automatic gearbox selector lever position ET108 Automatic gearbox selector lever position.
–Position of the manual gearbox selector lever (see 87G, Engine compartment connection unit, Conformity
check).
If the starting conditions are met, the request for the Protection and Switching Unit to activate the starter motor can
be viewed using status ET110 UCH request to injection or Protection and Switching Unit.
1.4 Main COMPONENTS of the ACCESS/SAFETY function
1.4.1 Main components of the ACCESS sub-function:
–Renault card,
–UCH,
–optical presence sensors located in the door handles,
–access aerials integrated in the door handles and the tailgate,
–the locking switches incorporated in the door handles,
–the boot-only opening/locking switch built into the boot badge,
–opening element locking motors.
1.4.1.1 The Renault card:
The Renault card has three buttons which allow:
–locking of the vehicle,
–unlocking of the vehicle,
–the boot to be locked/unlocked.
The Renault hands-free card allows hands-free operation if it is located in the access and starting zones.
The Renault card is powered by a 3 V battery. This battery is required for operation in hands-free mode or remote
control mode (card button presses).
If the battery is old or in an area of frequency interference, the emergency insert located in the Renault card allows
the driver's door to be unlocked.

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-35
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-35V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.4.3 Main components of the STARTING sub-function:
The starting sub-function is based on the following main factors:
–The starting conditions being present.
–Passenger Compartment Control Unit (UCH).
–The automatic gearbox computer (if fitted on the vehicle).
–The Protection and Switching Unit.
1.4.3.1 Start button:
The start button transmits the driver's requests to start or stop the engine to the UCH.
1.4.3.2 The UCH:
The UCH ensures that the starting conditions are met, and that no other computer on the multiplex network is
inhibiting starting of the vehicle.
If the conditions are met, it requests control of the starter from the UPC.
1.4.3.3 The Protection and Switching Unit (UPC):
The Protection and Switching Unit activates the starter motor following a request from the UCH via the multiplex
network.
1.4.3.4 Neutral sensor (manual gearbox):
Informs the UCH of the position of the gearbox (neutral or gear engaged).
1.4.3.5 Clutch switch (manual gearbox):
Sends clutch pedal depressed signal (end of travel) to the UCH.
1.4.3.6 Brake switch:
Sends brake pedal depressed signal to the UCH.
Operation:
The unknown status does not automatically require the brake pedal to be replaced, because it is a temporary
operating status between released pedal status and depressed pedal status (see diagram above).

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-36
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-36V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.4.3.7 Automatic gearbox computer (if fitted):
The computer informs the UCH of the selector position (park, neutral, etc.) via the multiplex network.
2 AIR CONDITIONING FUNCTION
The type of air conditioning control can be displayed by configuration reading LC013 Air conditioning type and
configured using command CF019 Air conditioning type (can be configured during configuration of the UCH
by the SC008 UCH type command).
2.1 Sub-function: USER SELECTION (Non-regulated air conditioning only)
The UCH receives the signal from the air conditioning panel via cable connection for the air conditioning request, for
electric heated rear screen and the signal for passenger compartment blower operation.
The UCH sends the request to the Protection and Switching Unit to start electric heated rear screen de-icing.
The UCH sends the request to the injection system to activate the air conditioning compressor.
The following statuses can be displayed:
–ET029 Air conditioning button.
–ET028 Heated rear screen button.
–ET015 Passenger compartment fan.
Operation of the indicator lights on the air conditioning and electric heated rear screen request buttons can be
checked using the following actuator commands:
AC015 Air conditioning button indicator and AC019 Heated rear screen indicator.
2.2 Sub-function: HEATING
The UCH manages the passenger compartment heating resistors (RCHs) by controlling power relays according to
the request for ventilation in the passenger compartment, the engine coolant temperature, the external temperature,
the electrical power balance, engine loading and, for the cabriolet version, if the roof is open.
The following statuses and parameters produced by the UCH can be displayed:
–PR001 Battery voltage.
–PR002 External temperature.
–ET015 Passenger compartment blower only with non-regulated air conditioning.
–ET017 Number of RCH*s required.
–ET018 Number of RCH*s authorised by alternator alternator charge rate.
–ET019 Number of RCH*s authorised by injection system.
–ET020 Number of RCH*s activated.
–ET021 RCH* 1 control.
–ET022 RCH* 2 control.
–ET031 Fast idle request for RCH.
–ET169 Engine.
–ET025 Retractable roof for cabriolet version only.
–ET026 Heated rear screen switch.
*RCH = Passenger Compartment Heating Resistors

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-37
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-37V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
Relay 1 controls a passenger compartment heating resistor unit consisting of one resistor.
Relay 2 controls a passenger compartment heating resistor unit consisting of two resistors.
Check the operation of the passenger compartment heating resistors using actuator commands:
AC016 RCH relay 1, AC017 RCH relay 2 and AC018 RCH relay 3.
The configuration can be displayed using LC030 Heating resistor types.
2.3 Sub-function: COLD LOOP
The UCH requests the injection to switch on the compressor via the multiplex network, depending on the external
temperature, the passenger compartment blower activation signal and whether the engine is in operation. The
following statuses and parameters can be displayed:
–ET030 Air conditioning request 2.
–ET169 Engine.
–ET015 Passenger compartment fan.
–PR002 External temperature.Passenger compartment
heating resistor powerRelay 1 Relay 2
0 W 0 0
333 W 1 0
667 W 0 1
1000 W 1 1

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-45
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-45V9 MR-372-J84-87B000$129.mif
4.4 Special features of the light sensor (if fitted to the vehicle).
Information displays Rain and light sensor Multiplex network
Steering column
controlUCHProtection and Switching
Unit
The rain and light sensor is a single sensor, connected to the UCH by a single connection. This sensor is installed on
the windscreen.
The light sensor enables the side lights and dipped headlights to be operated automatically as soon as the vehicle is
in a dark place (tunnel, night, gloomy weather conditions, etc.).
The status of the light sensor can be displayed using ET115 Lights on request by light sensor, and by configuration
reading LC044 Rain/light sensor.
Configuration CF035 Rain/light sensor is available during UCH configuration SC008 UCH type (see
Configurations and programming).
To activate the automatic lighting function, press the AUTO button on the lighting stalk for at least 4 seconds. This
action is confirmed by two beeps.
To deactivate the automatic lighting function, switch the engine off and press the AUTO button on the lighting stalk
for at least 4 seconds. A beep confirms this action and the message Automatic lighting OFF appears on the
instrument panel.
Any other operation on the lighting stalk overrides and cancels automatic operation.
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
Side lightsWindscreen
wiper
Dipped
headlights
Main beam
headlights