MG MG6 Series 2011 - Operation

EngineFuel&ManagementSystem
Engine
Operation
ECM-General
The
ECMmonitorstheconditionsrequiredforoptimum
combustionoffuelinthecylindersusingsensorslocatedat
pointsaroundtheengine.Fromthesesensorinputs,theECM
cancontrolandadjustthefuelquantityandtimingofthefuel
beingdeliveredtoeachcylinder.
TheECMcontainsanElectronicallyErasableProgrammable
ReadOnlyMemory(EEPROM)whichisprogrammedwithdata
requiredtoruntheengine.TheECMreceivesandstoresa
vehiclespecicsecuritycodefromtheimmobilisationmodule
duringproduction.TheECMcannotfunctionunlessitECMis
connectedtoanimmobilisationmodulewiththesamecode.
WhenreplacinganECMinservice,thenewunitissupplied
'blank'andmustbeprogrammedusingthediagnostictool.The
newunitmustlearnthesecuritycodefromtheimmobilisation
module.
The
ECMcontrolsthefollowing:
•Themainrelay
•Fuelpumpoperation
•Closedloopfuelling
•Openloopfuelling
•Ignitiontiming
•Idlespeedcontrol
•
EVAPcontrol
•Engineimmobilisation(inconjunctionwiththe
immobilisationmodule)
•Enginecoolingfanrelays
•A/Ccompressorclutchcontrol
TheECMsendsandreceivesinformationtoandfromthe
componentsandsignalsshowninthecontroldiagramandthe
followinginputandoutputtable:
InputsProcessorOutputs
BatteryvoltageECM
HandsetpositionFuelinjector
CKPsensorCoils
CMPsensors5Vsensorsupply
forTMAPsensor
TMAPsensor1ETB
TMAPsensor2ECTsignal
KnocksensorA/Ccompressor
clutchrelay
ECTsensorPurgevalve
HO2SHO2S
ETBBoostcontrol
solenoidvalve
A/CA/Cpressure
switch
Fuelpumprelay
PASPASpressure
sensor
Mainrelay
AlternatorloadCoolingfanrelays
Fueltanklevel
sender
MIL
Vehiclespeed
androughroad
signalsfromDSC
ABSECU
CANBus
Immobilisation
module
DiagnosticCAN
Bus
CANBus
DiagnosticCAN
Bus
Allsysteminputsareintheformofanalogueordigitalvoltage
signals,allsystemoutputsaredrivercircuitswhichsupplya
groundpathtotheexternalcomponent.TheoutputsarePulse
WidthModulatedPWMsignalswheretheoutputisregulated.
The
ECMinterfaceswiththefollowing:
•Diagnosticsviaconnectiontothediagnostictool
•A/C
•PAS
•Immobilisationmodule
•TCM
•Instrumentpack
•
BCM
•DSCABSECU
Withtheignitionon,theECMprimesthefuelsystemby
runningthefuelpumpforapproximatelytwoseconds.This
isachievedbycompletingthegroundpathforthefuelpump
relaycoil.TheECMreferencesthesensorspriortostartup.
WhenthehandsetismovedtotheCRANKposition,theECM
communicateswiththeimmobilisationmodule.Ifitreceives
authoritytostart,theECMbeginsignitionandfuellingwhen
CKPandCMPsensorsignalsaredetected.TheECMwill
operatethefuelpumpcontinuouslywhenavalidCKPsensor
signalisreceived.
Version2.0275