2008 RENAULT SCENIC lights

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-2
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-2V9 MR-372-J84-87B000$043.mif
187B
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction
1. SCOPE OF THIS DOCUMENT
This document presents the fault finding procedure applicable to all computers with the following specifications:
2. PREREQUISITES FOR FAULT FINDING
Documentation type:
Fault finding procedures (this document):
–Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
–Visu-Schéma (CD-ROM), paper.
Type of diagnostic tools:
–CLIP
Special tooling required:
3. REMINDERS
Procedure
To run fault finding on the vehicle computers, switch on the forced + after ignition feed.
Proceed as follows: Vehicle(s): Mégane II, Scénic II
Function concerned: UCHName of computer: UCH
Vdiag No.: 44, 48, 4C, 4D, 4F, 50.
Special tooling required
Multimeter
Elé. 1681 Universal bornier
Switch on the forced + after ignition feed:
–with the vehicle card in the card reader,
–press and hold start button (longer than 5 seconds) with start-up conditions not fulfilled,
–connect the diagnostic tool and perform the required operations.
Switching off the forced + after ignition feed:
Press the Start button twice briefly (less than 3 seconds).
ensure that the + after ignition feed has been cut off by checking that the computer indicator lights on the instrument
panel have gone out.
UCH_V44_PRELI /UCH_V48_PRELI/UCH_V4C_PRELI/
UCH_V4D_PRELI/UCH_V4F_PRELI/UCH_V50_PRELI
MR-372-J84-87B000$043.mif

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-7
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-7V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
General operation:
The UCH is involved in the following five functions (shared between several computers):
1/ Access-safety function
This function is divided into three sub-functions: Access, Protection and Starting.
2/ Air-conditioning function
This function is divided into three sub-functions, which are: User selection, Heating and Cold loop (see: 62A, Air
conditioning).
In this function, the UCH manages the triggering of the passenger compartment heating resistor control relays, as
well as the heated rear screen and air conditioning indicator lights.
3/ Wiping function
This function is divided into two sub-functions, which are: Wiper control and Wiper power.
4/ Lighting function
This function is divided into two sub-functions, which are: Lighting control and Lighting power.
5/ Tyre function
This function is divided into three sub-functions which are: Tyre reception, Tyre management and Tyre display.
MR-372-J84-87B000$086.mif
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-15
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-15V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.1.6 Principle of Electric Childproof Locking:
The UCH controls the rear door locks to prevent them from being opened by means of the interior door handles and
inhibits operation of the rear electric window switches.
The switch statuses and the activation of electric childproof locks can be viewed using the following statuses:
–ET233 Child safety lock switch,
–ET159 Rear left-hand door child safety lock,
–ET160 Rear right-hand door child safety lock.
The configuration Child safety lock can be read using configuration LC035 Child safety lock and modified (see
Configurations and programming) using the specific command SC016 Child safety lock (Vdiag 4C, 4D, 4F and
50).
Fault finding can be performed on the child safety lock switch indicator light using command AC076 Child safety
lock indicator light.
1.1.7 Principle of Deadlocking:
The UCH controls the door locks to prevent unlocking via the interior handles. This function is activated by pressing
and holding (+ 2 seconds) the Renault card's locking button or by pressing the door locking button twice.
The direction indicators flash rapidly three times for deadlocking (in addition to the two flashes for locking).
For this function to operate, the vehicle must have deadlocking (2 motors) and configuration LC003 Deadlocking
must be WITH (see Configurations and programming). Deadlocking is configured using CF009 Deadlocking.
The source of the last deadlocking activation/deactivation can be viewed using statuses ET088 Deadlocking
activation source and ET090 Deadlocking deactivation source.
It is impossible to deadlock the vehicle if the + accessories feed is active, if the lights are switched on or if the hazard
warning lights are activated.
1.1.8 The valet card function, specific to certain countries (e.g. Mexico):
This function controls the valet card option which enables vehicles fitted with it to separately control unlocking of the
driver's door, the boot, or the passenger doors and the glovebox.
When the vehicle is electrically pre-equipped with the valet option and this option has been configured, the cards can
be used in two different customer modes. The "master" cards can unlock all the opening elements, but the "valet"
cards cannot unlock the glovebox, the boot and the passenger opening elements. They can only start the vehicle,
lock the whole vehicle, and unlock the driver's door. The function is configured with CF085 Valet card function
using the specific command SC008 UCH type. To access CF085, configure CF036 Selective opening element
opening to WITH.
To check that this function has been configured correctly, use LC016 Card valet function.

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-22
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-22V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
1.1.13 Principle of automatic window relift:
When the doors are locked, and the lock button on the card is pressed twice in succession (or the door or boot if
the vehicle is fitted with hands-free function), the windows close automatically (as well as the sunroof, if fitted to
the vehicle).
The function is available on certain vehicles (see table below) depending on the number of one touch windows on
the vehicle and depending on the bodywork phases.
The automatic window relift function cannot be configured separately; it is automatically configured during special
command SC008 UCH type according to the vehicle type, number of one-touch windows and the production number
type.
1.1.14 Principle of new vehicle storage mode:
The vehicle is configured in this mode when it leaves the factory to optimise its power consumption:
–The immobiliser warning light is inhibited.
–The direction indicator warning lights are lit continuously on the instrument panel.
Before delivering the vehicle to the customer, deactivate this mode:
–By flipping down the steering column controls with the after ignition feed off.
–Or using command VP016 Deactivate new vehicle storage mode.
This function can only be activated in the factory with UCH Vdiag 4F or 50.If Then
Vehicle type One-touch window(s)Production
number typeFunction of automatic
window relift:
All except cabriolet phase 1 and 2
bodyworkWITHOUT WITHOUT
4-door phase 1 bodywork 1 driver OTW Jxxxxxx WITHOUT
4-door phase 1 bodywork 1 driver OTW OTHERS WITH
All except cabriolet and 4-door phase
1 bodywork1 driver OTW WITH
All except cabriolet phase 2 bodywork 1 driver OTW WITHOUT
All except cabriolet phase 1 and 2
bodywork2 or 4 OTW WITH
Cabriolet phase 1 and 2 bodywork WITHOUT WITHOUT

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-38
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-38V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
3 WIPER FUNCTION
3.1 Sub-function: WIPER CONTROL
The UCH receives the driver's request when the wiper stalk is used.
Windscreen wiper:
The UCH requests the Protection and Switching Unit via the CAN network to supply power to the windscreen wiper.
The park position is managed by the Protection and Switching Unit.
The wiper control stalk has four positions (neutral, intermittent wiping, slow speed and fast speed) and a wiper
intermittent speed ring which varies the time between each wipe.
Special notes:
If the windscreen wiper is set to low speed when the vehicle is moving and then the vehicle stops, the system switches
to intermittent wipe.
The requests made to the UCH by the wiper stalk can be displayed using statuses: ET077 Wiper stalk position and
ET096 Wiper intermittent speed ring.
If the vehicle is fitted with a rain sensor, (see special features of the rain and light sensor).
Rear screen wiper:
Rear wiper speed and power supply are also controlled by the UCH.
Windscreen wiper outside neutral position:
–The rear screen wiper starts to operate as soon as reverse gear is engaged and rain drops are detected on the
windscreen wiper.
–When the vehicle is stationary, the wipers operate intermittently every 7 seconds; over 36 mph (60 km/h) they
operate every 3 seconds. There is no continuous wiping function, except during the rear screen washer control.
The statuses corresponding to operation of the rear screen wiper can be displayed using statuses ET080 Rear
screen wiper request, ET097 Rear screen wiper park position and ET109 Reverse gear engaged or ET108
Automatic gearbox lever position, by configuration reading LC064 Rear screen wiper and by configuration
CF166 Rear screen wiper.
Windscreen washers:
The front and rear windscreen washers are controlled directly by the wiper control stalk, via a wire connection.
These connections are doubled up to the UCH to permit command status reading.
ET078 Windscreen washer request,
ET079 Rear screen washer request.
Special features of headlight washers
For vehicles fitted with xenon bulbs, the headlight washers are actuated at the same time as the windscreen washer,
only if the headlights are on.
Two cases are possible concerning the control of the headlight washers.
First case: (vehicles fitted with a SIEMENS Vdiag 44 UPC): the UCH sends the command by cable to two headlight
washer relays on a relay plate underneath the UPC.
Second case: (vehicles fitted with a LEAR Vdiag 48 or later): the UCH requests the UPC via the multiplex network to
activate the washer relays.
WARNING
If the UCH does not manage to determine the position of the control stalk, or inform the Protection and Switching
Unit of the control stalk's position, the Protection and Switching Unit will activate the windscreen wiper at low speed
(defect mode).
MR-372-J84-87B000$129.mif

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-39
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-39V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
3.2 Sub-function: WIPER POWER
The UCH controls the rear screen wiper's power (and that of the headlight washers if the vehicle is fitted with xenon
headlights and a SIEMENS Vdiag 44 UPC).
Their operation can be checked using commands AC007 Rear screen wiper, AC030 Headlight washer relay 1
and AC031 Headlight washer relay 2.
Rain and light sensor
Information displays Multiplex network
Steering column
control
UCH Protection and
Switching Unit
Rear screen wiper Rear screen wiper
Windscreen and rear
screen washers
Headlight
washers

PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-40
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-40V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
3.3 Special features of the rain sensor (if fitted to the vehicle)
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 rain sensor enables the windscreen wipers to be operated automatically and controls the wiper speeds according
to the quantity of water on the windscreen.
The sensor is activated by setting the wiper stalk to AUTO position.
Depending on the vehicle's bodywork, two cases are possible for the operation of the rain sensor:
a) Phase 1 bodywork:
Automatic operation of the rain sensor is inhibited following ignition switch-off with the wiper stalk in the Auto position.
To reactivate operation when next switching on the ignition, set the wiper control stalk in the neutral position then
return it to the Auto position.
b) Phase 2 bodywork:
Automatic operation of the rain sensor remains active following ignition switch-off with the wiper stalk in the Auto
position.
For a vehicle which is fitted with a rain sensor, with automatic detection activated, the rear screen wiper starts to
operate if reverse gear is engaged and if the sensor has detected rain for more than 1 minute.
The wiper intermittent speed ring is used to modify the sensor's sensitivity to rain and therefore the time
between wipes.
When the vehicle is not fitted with a rain sensor, the intermittent speed position on the control stalk takes the place of
the Auto position.
The status ET118 Rain sensor sensitivity ring position can be interpreted if the vehicle is configured with rain
sensor and inhibits status ET096 Intermittent wipe ring position.
The operation of the rain sensor can be displayed using status ET114 Wiper request by rain 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). Information displays Rain and light sensor Multiplex network
Steering
column
control UCH Protection and Switching Unit
Side lights Windscreen wiper
Dipped headlights
Main beam headlights