Navistar MaxxForce 9

SECTION1–ENGINESYSTEMS
ElectronicGovernorControl
Thegovernorcontrolsenginerpmwithinasafeandstable
operatingrange.
Thelowidlegovernorpreventsenginerpmfromdropping
belowastablespeedtopreventstallingwhenvariousloadsare
demandedontheengine.
Thehighidlegovernorpreventsenginerpmfromgoingabovea
safespeedthatwouldcauseenginedamage.
ElectronicServiceTool(EST)Interface
EnginesareequippedwiththeESTinterfaceforcommunication
betweentheEngineControlModule(ECM)andtheEST .
CANisaJ1939serialbussystem,alsoknowastheDrivetrain
Datalink.ThepublicControllerAreaNetwork(CAN)providesa
communicationlinkbetweenallconnectingmodulesbysending
andreceivingmessages.
TheESTwithServiceMaxx™softwarecommunicateswiththe
ECMthroughtheESTinterface.TheEST,throughthepublic
CAN,isabletoretrieveDiagnosticTroubleCodes(DTCs),run
diagnostictests,andviewParameterIdentiers(PIDs)fromall
inputsandoutputsoftheECM.
CANpublicsupportsthefollowingfunctions:
•Transmissionofengineparameterdata
•TransmissionandclearingofDTCs
•Diagnosticsandtroubleshooting
•Programmingperformanceparametervalues
•Programmingengineandvehiclefeatures
•ProgrammingcalibrationsandstrategiesintheECM
ElectronicSpeedometerandTachometer
Theenginecontrolsystemcalibratesvehiclespeed.The
calculatedvehiclespeedisafunctionoftransmissiontailshaft
speed,numberofteethonthetailshaft,rearaxleratio,andtire
revolutionspermile.UsetheElectronicServiceT ool(EST)with
ServiceMaxx™softwaretoprogramnewspeedcalibrationsinto
theECM.
ThetachometersignalisgeneratedbytheECMbycomputing
signalsfortheCamshaftPosition(CMP)sensorandCrankshaft
Position(CKP)sensor.
EngineCrankInhibit(ECI)
ECIpreventsstarterengagementwhentheengineisrunningor
whenthetransmissionisingear.
EventLoggingSystem
Theeventloggingsystemrecordsengineoperationabove
maximumrpm(overspeed),lowcoolantlevel,highcoolant
temperature,orlowoilpressure.Thereadingsfortheodometer
andhourmeterarestoredintheECMmemoryatthetimeofan
eventandcanberetrievedusingtheEST .
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