lights RENAULT SCENIC 2008 J84 / 2.G Engine Compartment Connection Unit Workshop Manual

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87G
87G - 3V7 MR-372-J84-87G050$055.mif
UPC
Vdiag No.: 48, 4C
3. REMINDER
PROCEDURE
To run fault finding on the vehicle's computers, switch on the ignition in fault finding mode (forced + after ignition
feed). Run the self-test procedure for the UPC internal relays and fuses using AC016 Electrical supply circuit
test.
Depending on the type of vehicle equipment, proceed as follows:
To cut off the + after ignition feed, proceed as follows:
Faults
Faults are declared as either present or stored (depending on whether they appeared in a certain context and have
disappeared since, or whether they remain present but have not been diagnosed within the current context).
The present or stored status of faults should be taken into consideration when the diagnostic tool is used following
the + after ignition supply being switched on (without operating the system components).
For a present fault, apply the procedure described in the Interpretation of faults section.
For a stored fault, note the faults displayed and apply the instructions in the Notes section.
If the fault is confirmed when the instructions in the Notes section are applied, the fault is present. Deal with the fault
If the fault is not confirmed, check:
–the electrical lines which correspond to the fault,
–the connectors on these lines (corrosion, bent pins, etc.),
–the resistance of the component detected as faulty,
–the condition of the wires (melted or split insulation, wear). WARNING
Switch off all unnecessary consumers:
–Radio navigation system.
–Switch the passenger compartment ventilation speed to 0.
–Switch off the interior lights (forced off).
With the vehicle card in the card reader, press and hold the start button (+ 5 seconds) outside starting conditions,
connect the diagnostic tool and carry out the required operations.
Press the start button twice briefly (less than 3 seconds); check that the + after ignition feed has cut (computer
indicator lights on the instrument panel go out).

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - System operation87G
87G-8V7 MR-372-J84-87G050$110.mif
UPC
Vdiag No.: 48, 4CENGINE COMPARTMENT CONNECTION UNIT
Fault finding - System operation
General operation
The Protection and Switching Unit is involved in the following functions:
–Access - Safety.
–Air conditioning.
–Lighting.
–Wipers.
–Charging circuit.
–Oil pressure detection.
–Electric power distribution.
1 - Electric power distribution
The main function of the Protection and Switching Unit is to switch and distribute the power supply to the vehicle's
systems, actuators or computers.
Part of this function is handled within the unit, but it is not electronically controlled by the computer.
+ 12 V battery feed
The Protection and Switching Unit receives energy from the battery via the Busbar and MM connectors (tracks 6 and
4) and redistributes the + 12 V feed.
+ 12 V after ignition
The UCH sends the Protection and Switching Unit the + 12 V after ignition feed request via the multiplex network.
When the Protection and Switching Unit receives this request, it actuates the after ignition relay unconditionally. The
signal is distributed to the sensors, actuators and computers.
2 - Charge circuit
One of the main functions of the Protection and Switching Unit is managing the charge circuit.
Purpose and components:
The main function of the charging circuit is to produce and distribute the electrical energy required to operate the
various electrical consumers on the vehicle (computers, lights, etc.).
It is also used to start the engine.
The main components are a battery, an alternator and a starter motor.
MR-372-J84-87G050$110.mif

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - System operation87G
87G-11V7 MR-372-J84-87G050$110.mif
UPC
Vdiag No.: 48, 4C
5 - Exterior lighting
The Protection and Switching Unit receives lighting requests from the UCH via the multiplex network.
The computer then switches the power relays:
–side lights,
–dipped headlights,
–main beam headlights,
–front fog light.
For the operation of this function and the role of the Protection and Switching Unit in the control of this function,
(see 80D, Lighting).
6 - Wiping - Washing
The Protection and Switching Unit receives wiping requests from the UCH via the multiplex network.
The computer then switches the power relays:
–low or high-speed windscreen wiper,
–headlight washers pump relay.
–The Protection and Switching Unit also receives the windscreen wiper park position signal. Using this signal the
computer can determine whether the blade is jammed, and decide whether to stop the wiper motor to protect it.
For the operation of this function and the role of the Protection and Switching Unit in the control of this function,
(see 85A, W ipers-Washing).
7 - Oil pressure detection
The Protection and Switching Unit receives the oil pressure sensor signal and distributes it over the multiplex
network.
8 - Reverse gear engaged signal
The Protection and Switching Unit receives the reverse gear engaged position sensor signal and distributes it over
the multiplex network.

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Configurations and programming87G
87G-14V7 MR-372-J84-87G050$220.mif
UPC
Vdiag No.: 48, 4CENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Configurations and programming
This operation is used to configure the Protection and Switching Unit to the equipment present in the vehicle.
Procedure to follow for modifying these configurations:
●Establish dialogue with the UPC.
●Select the repair mode menu.
●Select the configure menu.
●Select line VP004 Vehicle parameters.
●Select the line corresponding to the vehicle equipment from the drop-down menus.
●Confirm the configurations selected and then click on validate.
●Switch the ignition off and then back on for the configurations to be recognised by the computer.
●In the configuration reading menu, check that each configuration has been performed.
Make sure that all the vehicle's equipment is working.Equipment required
CLIP diagnostic tool
Configuration Configuration reading Name of configuration
Automatic
(the alternator is
automatically recognised
by the Protection and
Switching Unit)LC001 Type of alternator
VP004 LC008 Gearbox type
VP004 LC007 Front fog lights
VP004 LC013 Headlight washers
MR-372-J84-87G050$220.mif

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults87G
87G-22V7 MR-372-J84-87G050$330.mif
UPC
Vdiag No.: 4C
DF009
PRESENT
OR
STORED+ APC CIRCUIT
1.DEF: Permanent low level
2.DEF: Permanent high signal
NOTESSpecial note:
This fault only applies to Vdiag 4C.
Conditions for applying the fault finding procedure to present faults:
The fault is declared present after the ignition has been switched on.
Use Wiring Diagrams Technical Note for Mégane II or Scénic II.
Check the connection and condition of the LPG electric control unit connector, component code 997.
Check for a voltage on connection AP31 to the connector for the LPG electric control unit, component code 997.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check the connection and condition of the multifunction switch, the reverse gear switch and the manual
gearbox neutral sensor/reversing lights, component codes 485, 155, and 1109.
Check for a voltage on connection AP11 to the connectors for the multifunction switch, the reverse gear switch
and the manual gearbox neutral sensor/reverse lights, component codes 485, 155, and 1109.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check the connection and condition of the passenger compartment electric control unit, component code 645.
Check for a voltage on connection APCB to the connector for the passenger compartment electric control unit,
component code 645.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check the connection and condition of the electric steering column lock, component code 1088.
Check for a voltage on connection AP15 to the connector for the electric steering column lock, component code
1088.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check the connection and condition of the airbag/pretensioner electric control unit and the electric power-
assisted steering system, component codes 756 and 1232.
Check for a voltage on connection AP44 to the connectors for the airbag/pretensioner electric control unit and
the electric power-assisted steering system connectors, component codes 756 and 1232.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
AFTER REPAIRErase the faults from the computer memory, switch the + after ignition supply off and
back on again and run another check using the diagnostic tool.
USM_V4C_DF009

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults87G
87G-24V7 MR-372-J84-87G050$330.mif
UPC
Vdiag No.: 48, 4C
DF012
PRESENT
OR
STOREDALTERNATOR
1.DEF: Alternator mechanical or electrical fault
NOTESConditions for applying the fault finding procedure to present faults:
The fault is declared present after the engine has been running for at least 1 minute.
Special note:
The fault illuminates the Battery and STOP warning lights on the instrument panel.
Use Wiring Diagrams Technical Note for Mégane II or Scénic II.
1.DEF
NOTESNone.
Check the fitting, condition and tension of the accessories drive belt.
Visually check that the alternator is not clogged.
Clean out the alternator cooling vents using an air gun.
Check the wiring, the connections and the earths (see Test no. 1 Wiring test).
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Run command AC014 Alternator regulation (see Interpretation of commands).
With the bonnet closed, start the engine.
Leave the engine to run for 2 minutes at idle speed.
If the fault is still present, replace the alternator (see MR 364 or MR 370 Mechanical, 16A, Starting - Charging,
Alternator: Removal - Refitting).
AFTER REPAIRErase the faults from the computer memory, switch the + after ignition supply off and
back on again and run another check using the diagnostic tool.
USM_V48_DF012/USM_V4C_DF012

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults87G
87G-38V7 MR-372-J84-87G050$330.mif
UPC
Vdiag No.: 48, 4C
DF020
PRESENT
OR
STOREDFRONT FOG LIGHT CIRCUIT
CO: Open circuit
CC.0: Short circuit to earth
CO
NOTESSpecial note:
To display this fault as present or stored, run the command
AC016 Electrical supply circuit test.
Use Wiring Diagrams Technical Note for Mégane II or
Scénic II.
Check that the front fog light bulbs are sound.
Repair if necessary.
Check the condition and connection of the 2-track connectors for the front fog lights, component code 176 and
177 (tabs broken, bent or oxidised).
If the connector is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the connector, otherwise replace the connector.
Check that the earth on connection code MAS for the front right-hand fog light, component code 176 is perfect.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check that the earth on connection code MAS for the front left-hand fog light, component code 177 is perfect.
If the connection is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring otherwise replace the wiring.
Check the condition and connection of the 8-track connector AN for the Protection and Switching Unit,
component code 1337 (tabs bent, broken, oxidised).
If the connector is faulty and if there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the connector, otherwise replace the connector.
Check the insulation, continuity and the absence of interference resistance on the following connections:
–8E between components 1337 and 177,
–8F between components 1337 and 176.
If the connection or connections are faulty and if there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check the fitting and switch for the front fog lights.
Repair if necessary or replace the light(s) if faulty.
If the fault is still present, contact the Techline.
AFTER REPAIRRun command AC016 "Electrical supply circuits test".
Erase the faults from the computer memory, switch the + after ignition supply off and
back on again and run another check using the diagnostic tool.
USM_V48_DF020/USM_V4C_DF020

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check87G
87G-61V7 MR-372-J84-87G050$440.mif
UPC
Vdiag No.: 48, 4C
FUNCTION: LIGHTING
SUB-FUNCTION: LIGHTING POWER
NOTESOnly carry out this conformity check after a complete check with the diagnostic tool
(fault reading and configuration checks).
Application conditions: engine stopped, + after ignition feed on.
FunctionParameter or Status
Check or ActionDisplay and Notes Fault finding
Side lightsAC003:Side lightsThis command
switches on the side
lights.In the event of a fault, apply the
procedure for dealing with
command AC003.
Dipped
headlightsAC002:Dipped
headlightsThis command
switches on the dipped
beam headlights.In the event of a fault, apply the
procedure for dealing with
command AC002.
Main beam
headlightsAC001:Main beam
headlightsThis command
switches on the main
beam headlights.In the event of a fault, apply the
procedure for dealing with
command AC001.
Front fog lightsAC004:Front fog lightsThis command
switches on the front
fog lights.In the event of a fault, apply the
procedure for dealing with
command AC004.

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of statuses87G
87G-66V7 MR-372-J84-87G050$550.mif
UPC
Vdiag No.: 48, 4C
ET004
REVERSE GEAR ENGAGED
NOTESSpecial notes:
Only apply the checks with the ignition switched on and when no faults are present.
Use Wiring Diagrams Technical Note for Mégane II or Scénic II.
5- and 6-speed manual gearbox
Check the condition and connection of the connector of the reverse gear switch, component code 155, the
manual gearbox neutral/reversing lights sensor, component code 1109, and UPC connector MN,
component code 1337.
If the connector is faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the connector, otherwise replace the connector.
With the ignition on and reverse gear engaged, check for + 12 V on connection codes H66P and AP11 of
Protection and Switching Unit connector MN, component code 1337.
If the connection is faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check the insulation, continuity and the absence of interference resistance on the following connections:
–AP11 between components 1337 and 1109,
–H66P between components 1337 and 1109.
Reverse gear engaged:
–between AP11 and H66P on component 155.
If the connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the fault is still present, contact the Techline.
AFTER REPAIRRepeat the conformity check from the start.
USM_V48_ET004 /USM_V4C_ET004

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of statuses87G
87G-69V7 MR-372-J84-87G050$550.mif
UPC
Vdiag No.: 48, 4C
ET023
ALTERNATOR THERMAL FAULT
NOTESSpecial notes:
Apply the checks if the status is PRESENT with the engine running.
Switch off the engine.
Check the general condition of the alternator:
Make sure that there are no foreign bodies that could impair the alternator cooling.
Clean the alternator if necessary.
With the engine stopped, let the alternator cool down with the bonnet open for at least 1 hour.
Start the engine with the bonnet closed.
Switch on the main beam headlights and the electrical heated rear screen.
If the status becomes PRESENT again, replace the alternator (see MR 364 or MR 370 Mechanical, 16A,
Starting - Charging, Alternator: Removal - Refitting).
AFTER REPAIRRepeat the conformity check from the start.
USM_V48_ET023 /USM_V4C_ET023