Allison Transmission T 375

4.1.3.1SHIFTSELECTORTRANSITIONANDOILFIELDPUMPING
(INPUTFUNCTIONBZ:WIRE142)(OFSModels)
WARNING:Thisinputfunctioninvolvestheuseofcomplex
algorithmsinthecontrollogic.Ifthefunctionisenabledinthe
calibrationbutthecontrolcircuitforthefunctionisnotinstalled,there
isapotentialriskforoneormoresystemfailuremodeswhichcould
resultinundesirabletransmissionoperation.Therefore,theactivation
circuitforthisfunctionMUSTBEproperlyintegratedinthevehiclein
whichitisinstalled.Ifthefunctionwillnotbeusedinthenalvehicle,
itMUSTNOTbeorderedinthecalibration.Forspecicinstallations,
thevehiclemaybeoperatedpriortofullintegrationofthefunction
intothevehiclewiring.Forexample,abarechassistransportedto
abodybuilderwherethefunctionwillbewiredintothecompleted
vehicle.Inthesecases,ifthefunctionisactivatedinthecalibration,
thespecicwiresrelatedtothefunctionmustbeelectricallyisolated,
completelyandindividually.Untilproperlyintegratedintothenal
vehiclewiring,thechassisbuildermustprotectthewiressuchthat
theydonotmakeelectricalcontactwiththefollowing:
•eachother,ifthefunctioninvolvesmorethanonewire
•anyothertransmissionwiring
•anyothervehiclewires
•anypartofthevehicleorchassis
Description:ThisfunctioncombinesthefeaturesofSecondaryShift
Schedule(InputA)andShiftSelectorTransition(InputD)intooneswitched
inputandisintendedforuseONLYindual-modeapplicationsofOFS
transmissions.Thefunctionisenabledwhenthetransfer-caseactivated
switchisclosedtocompletethecircuitbetweenwire142andground.The
transitionispermittedonlywhenN(Neutral)isselectedandattainedinthe
transmission,andwhentransmissionoutputspeedisbelow60rpm.
Whenthefunctionisdisabled,thetransmissionoperatesaccordingtothe
primaryshiftscheduleprogrammedintheTCMandoperatorselectionson
shiftselector1.Shiftselector1mustbelocatedinthevehiclecab.Primary
(ROAD)ModemustbeusedONLYforvehiclepropulsion.
Whenthefunctionisenabled,thetransmissionoperatesaccordingtothe
secondaryshiftscheduleandcontrolofthetransmissiontransitionstoshift
selector2(whichmustbelocatedoutsidethevehiclecab).Secondary(RIG)
Mode,whichisprogrammedwithspecialcalibrationcharacteristicsand
diagnosticsforthisapplication,mustbeusedONLYforstationaryoperation
suchaspumping,swabbing,orwinching.
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