ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - System operation87G
87G-10V7 MR-372-J84-87G050$110.mif
UPC
Vdiag No.: 48, 4C
Only on vehicles with M9R injection:
The injection computer also acts on the alternator regulation voltage. The injection computer sends the maximum
authorised power delivered by the engine, to the UPC computer via the multiplex network. If the power from the engine
is less than the power consumed by the alternator, the UPC computer will reduce the alternator voltage.
For vehicles with any injection type except M9R:
The UPC sends the alternator charge to the injection to regulate the idling speed.
c) Starter
This turns the engine over to make it start, and requires a very powerful electric current, which the battery must be
able to supply.
The computer receives the starter activation request via the multiplex network from:
–injection,
–UCH,
–the automatic gearbox.
(see ET010 Starting conditions met)
The computer controls the starter relay.
In the event of a fault with the starter, refer to section 16A, Starting - Charging, Starter.
3 - Keyless vehicle
Under the keyless vehicle function, the Protection and Switching Unit is involved in the starting sub-function. The
computer:
–receives the supply request from the passenger compartment starter via the multiplex network, as well as the clutch
pedal position,
–controls the starter relay,
–inhibits or cuts out this relay control according to a signal prohibiting starting which is sent by the injection computer
or gearbox via the multiplex network (see 87B, Passenger compartment connection unit).
4 - Air conditioning
For the operation of the air conditioning and the role of the Protection and Switching Unit in the control of this
function (see 62A, Air conditioning).
Cold loop:
The computer receives the compressor switch-on request from the injection via the multiplex network.
The computer controls the compressor clutch engagement relay.
Heating:
The computer manages the alternator charge and sends back the signal over the multiplex network.
The computer also controls the rear screen de-icing.
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Conformity check87G
87G-57V7 MR-372-J84-87G050$440.mif
UPC
Vdiag No.: 48, 4C
KEYLESS VEHICLE
SUB-FUNCTION: STARTING
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
Reverse gearET004:Reverse gear
engagedYES
NOIn the event of a fault, refer to the
interpretation of status ET004.
Manual gearbox
lever positionET005:Manual gearbox
lever positionNOT IN NEUTRAL
NEUTRALNormal statuses.
UNAVAILABLE
INVALIDIn the event of a fault, refer to the
interpretation of status ET004.
Starting
conditions metET010:Starting
conditions metSTATUS 1
STATUS 2
STATUS 3In the event of a fault, consult the
interpretation for status ET010.
YESNormal status.
+ 12 V after
ignition feed
relay controlET003:+ 12 V after
ignition feed relay
control INACTIVE
ACTIVEIn the event of a fault, consult the
interpretation of fault DF032.
