radio 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-9V7 MR-372-J84-87G050$110.mif
UPC
Vdiag No.: 48, 4C
a) Battery
The principal purpose of the battery is to provide the powerful current briefly required by the starter motor to start the
engine. For optimum starting, the current supplied by the battery must be sent to the starter motor with minimum
loss. To achieve this, the electrical connections (wires, terminals, connectors, etc.) must be in good condition.
When the engine is not running, the battery must feed the accessories that operate constantly, even with the ignition
switched off, such as the alarm, radio codes, computers, etc.
–PR004 Battery voltage represents the supply voltage of the Protection and Switching Unit.
–PR008 Battery voltage after rest represents the battery charge status. If PR008 is less than 12.1 V
(battery discharged) during the first few miles, a "Charge battery" message is displayed on the instrument panel.
The Protection and Switching Unit determines what the voltage across the battery terminals should be, based on the
battery charge status, the operating phase and the battery temperature.
To obtain this voltage, the Protection and Switching Unit actuates the alternator.
b) Alternator
The alternator only operates when the engine is running. Its function is to recharge the battery, and at the same time
to supply the electrical power required to operate all the electrical accessories on the vehicle.
The Protection and Switching Unit is linked to the alternator by a serial connection. The Protection and Switching
Unit and the alternator communicate via this connection.
Alternator management is therefore completely new in relation to previous Renault vehicles.
The Protection and Switching Unit intelligently manages the alternator regulation voltage according to the engine
phase, the battery charge and the temperature.
The alternator sends the Protection and Switching Unit the following signals:
–Type of alternator: the Protection and Switching Unit configures itself according to the alternator specifications.
The Protection and Switching Unit can detect electrical or communication faults on this connection and signal them
using fault DF007 UPC - Alternator connection.
When the battery charge and PR008 Battery voltage after rest decline, the Protection and Switching Unit can
temporarily increase the alternator voltage by 1 V for a duration of 30 minutes after starting.
Before the engine is started and during starting, the alternator voltage is fixed at 10.6 V.
A maximum of 30 seconds after the engine is started, the Protection and Switching Unit sets the alternator voltage
at the optimum calculated value.Note:
A battery must always be fully charged, even when stored.

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults87G
87G-23V7 MR-372-J84-87G050$330.mif
UPC
Vdiag No.: 4C
DF009
CONTINUED
Check the connection and condition of the passenger compartment fuse and relay box, the gear lever display,
the steering column top control module, the additional heater relay 1 and 2, the diagnostic socket, the
parking distance control ECU, the right and left-hand rear electric window switch, the radio, the electric
door mirror control, the front and rear electric window locking controls and the passenger electric window
switch, component codes 260, 1129, 1546, 1067, 1068, 225, 1222, 130, 131, 261, 134, 135, 1511, 1512
and 133.
Check for a voltage on connection AP43 to the connectors for the passenger compartment fuse and relay box,
the gear lever display, the steering column top control module, the additional heater relay 1 and 2, the
diagnostic socket, the parking distance control ECU, the right and left-hand rear electric window switch,
the radio, the electric door mirror control, the front and rear electric window locking controls, the
passenger electric window switch, component codes 260, 1129, 1546, 1067, 1068, 225, 1222, 130, 131, 261,
134, 135, 1511, 1512 and 133.
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 insulation, continuity and the absence of interference resistance on the following connections:
–AP31 between components 1337 and 997,
–AP11 between components 1337, 485, 155 and 1109,
–APCB between components 1337 and 645,
–AP15 between components 1337 and 1088,
–AP44 between components 1337, 756 and 1232,
–AP43 between components 1337, 260, 1129, 1546, 1067, 1068, 225, 1222, 130, 131, 261, 134, 135, 1511, 1512
and 133.
If the 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 connection and condition of the Protection and Switching Unit, component code 1337.
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.
If the fault is still present, contact the Techline.
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.

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of parameters87G
87G-72V7 MR-372-J84-87G050$660.mif
UPC
Vdiag No.: 48, 4CENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of parameters
PR004
BATTERY VOLTAGE
NOTESSpecial notes:
Check that all of the electrical consumers are switched off:
–Passenger compartment blower unit stopped.
–Radio off (and Radio navigation system if fitted to the vehicle).
–Interior lights off.
If fault DF013 Voltage regulation is not present (or stored):
With the engine stopped and no electrical consumers operating for 5 minutes.
Check the battery, see TEST3 Battery status test.
If fault DF013 Voltage regulation is present:
With the engine running at idle speed, and electrical consumers activated:
–Dipped headlights and side lights.
–Electric heated rear screen.
–Passenger compartment blower unit in maximum position.
Check the consistency between the battery voltage measurement from the multimeter and the value of PR004
Battery voltage.
If the difference is greater than 1 V check the conformity of the Protection and Switching Unit supply circuit and
the charging circuit wiring TEST2 Wiring test.
Repair if necessary, otherwise replace the Protection and Switching Unit (see Replacement of components).
AFTER REPAIRRepeat the conformity check from the start.
USM_V48_PR004 /USM_V4C_PR004
MR-372-J84-87G050$660.mif

ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Fault finding charts87G
87G-91V7 MR-372-J84-87G050$880.mif
UPC
Vdiag No.: 48, 4C
ALP3No backlighting of the various functions in the passenger
compartment
NOTESMake sure that the side lights are working; if not, refer to the procedure for command
AC003 Side lights.
Use Wiring Diagrams Technical Note for Mégane II or Scénic II.
Check the condition and connection of the defective functions.
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.
Check for earth on the defective function(s).
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.
With the side lights on, check for 12 V on the defective function(s).
If correct, replace the defective component.
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 between the defective function
and the Protection and Switching Unit:
Right-hand headlight component code 226, rear right-hand
lights component code 172, right-hand and left-hand heated
seat control component codes 1513 and 1514, parking distance
control switch component code 1540, cruise control/speed
limiter control component code 1081, ESP on/off button
component code 1106, gear lever display component code
1129, hard roof switch component code 1482, simultaneous
window control component code 854, LPG or petrol selector
switch component code 1003, right-hand number plate light
component code 166.LPDConnector CN of the
Protection and Switching
Unit, component code
1337.
Left-hand rear light component code 173, left-hand headlight
component code 227, child safety switch component code 135,
CD changer component code 1272, radio component code
261, multifunction display component code 653, headlight
adjustment rheostat switch component code 1390, warning/door
locking switch component code 1391, first cigarette lighter
component code 101.LPGConnector CN of the
Protection and Switching
Unit, component code
1337.
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 REPAIRCheck that no fault is present.
USM_V48_ALP3 /USM_V4C_ALP3