Page 3 of 56

87G - 3
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Introduction
87G
V6 MR-372-J84-87G000$066_eng.mif
UPC
Vdiag No.: 44
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 the fault should be taken into consideration when the diagnostic tool is used after
the + after ignition feed has been connected (without any of the system components being activated).
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).
Conformity check
The aim of the conformity check is to check statuses and parameters that do not produce a fault display on the
diagnostic tool when they are inconsistent. Therefore, this phase is used to:
–carry out fault finding on faults that do not have a fault display, and which may correspond to a customer
complaint.
–check that the system is operating correctly and that there is no risk of a fault recurring after repair.
This section gives the fault finding procedures for statuses and parameters and the conditions for checking them.
If a status is not behaving normally or a parameter is outside the permitted tolerance values, consult the
corresponding fault finding page.
Customer complaints - Fault finding chart
If the test with the diagnostic tool is OK but the customer complaint is still present, the fault should be dealt with by
customer complaints.
A summary of the overall procedure to follow is provided on the following
page in the form of a flow chart.
Page 16 of 56
87G - 16
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
MAIN SCREEN
NOTESOnly check conformity after a complete check using the diagnostic tool.
Test conditions: Engine stopped, ignition on.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1Charging circuitET001:Battery warning
lightLIT
In the event of a fault, refer to
the relevant fault finding
method. 2Oil pressure
contactET027:Oil pressure
contactCLOSED
3GearboxET004:Reverse gear
engagedYES
NO
MR-372-J84-87G000$528_eng.mif
Page 17 of 56
87G - 17
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
KEYLESS VEHICLE: Starting the engine
NOTESOnly check conformity after a complete check using the diagnostic tool.
Test conditions: Engine stopped, ignition on.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1GearboxET004:Reverse gear
engagedYES
NO
In the event of a fault, refer to
the relevant fault finding
procedure. ET005:Manual gearbox
leverNEUTRAL
OUT OF NEUTRAL
NOT SUPPORTED, if
the vehicle is fitted with
an automatic gearbox
2StartingET010:Conditions for
engine start
satisfied.YES, if the conditions
for engine start have all
been satisfied and
after pressing the start
button
NO, if the engine start
conditions have not all
been satisfied or if the
engine start button has
not been pressed
Page 18 of 56

87G - 18
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
AIR CONDITIONING: Heating
AIR CONDITIONING: Cold loop
NOTESOnly check conformity after a complete check using the diagnostic tool.
Test conditions: Engine stopped, ignition on.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1StartingPR010:AlternatorIn %
The value must be
fixed and greater than
98%
Refer to the relevant fault
finding procedure in the
event of a fault.
AC011:Rear
windscreen
de-icingThe rear window
heating resistors and
the door mirrors (if the
vehicle is fitted with
heated door mirrors)
must be supplied with
power and heated.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1Fan assemblyAC009:Low speed fan
unitIt must be possible to
hear the fan running at
low speed.
Refer to the relevant fault
finding procedure in the
event of a fault. AC010:High speed fan
unitIt must be possible to
hear the fan running at
high speed
This command cannot
be used on vehicles
not fitted with climate
control
2Air conditioningAC008:Compressor
commandThe compressor clutch
must be heard (the
compressor command
is not permitted when
the engine is running)
Page 19 of 56
87G - 19
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
WIPERS: Wiper power
NOTESOnly check conformity after a complete check using the diagnostic tool.
Test conditions: Engine stopped, ignition on.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1Park positionAC012:Windscreen
wiper park
position testThe front windscreen
wiper must run for a
single sweep and
return to its initial
position.
Refer to the relevant fault
finding procedure in the
event of a fault. 2Wiper protectionET002:Front
windscreen
wiper protectionINACTIVE
3WipersAC005:Low-speed
windscreen
wiperThe windscreen wiper
must work at low
speed.
AC006:High-speed
windscreen
wiperThe windscreen wiper
must work at high
speed.
Page 20 of 56
87G - 20
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
LIGHTING: Lighting power
NOTESOnly check conformity after a complete check using the diagnostic tool.
Test conditions: Engine stopped, ignition on.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1LightingAC003:Side lightsThe front and rear side
lights and the number
plate lights as well as
the controls and
switches in the
passenger
compartment must
light up.
Refer to the relevant fault
finding procedure in the
event of a fault.
AC002:Dipped beam
headlightsThe dipped beam
headlights must come
on.
AC001:Main beam
headlightsThe main beam
headlights must come
on.
AC004:Front fog lightsThe front fog lights
must come on.
Page 21 of 56
87G - 21
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
MAIN SCREEN
NOTESOnly check conformity after a complete check using the diagnostic tool.
Condition for carrying out this operation: the engine must be running.
Order FunctionParameter or Status
checked or Action Display and notes Fault finding
1Charging circuitET001:Battery warning
lightOFF
Refer to the relevant fault
finding procedure in the
event of a fault. 2Oil pressure
contactET027:Oil pressure
contactOPEN
3GearboxET004:Reverse gear
engagedYES
NO
Page 22 of 56
87G - 22
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check
87G
V6 MR-372-J84-87G000$528_eng.mif
UPC
Vdiag No.: 44
KEYLESS VEHICLES: Starting the engine
NOTESOnly check conformity after a complete check using the diagnostic tool.
Condition for carrying out this operation: the engine must be running.
Order FunctionParameter or Status
checked or Action Display and Notes Fault finding
1GearboxET004:Reverse gear
engagedYES
NO
Refer to the relevant fault
finding procedure in the
event of a fault. ET005:Manual gearbox
leverNEUTRAL
OUT OF NEUTRAL
NOT SUPPORTED, if
the vehicle is fitted with
an automatic gearbox
2StartingET010:Conditions for
starting the
engine satisfied.YES, if the conditions
for starting the engine
have been met and
after a press on the
engine start button
NO, if the conditions
for starting the engine
have not been met or if
the engine start button
has not been pressed