Allison Transmission T 270 User Manual

•Directionchangeinhibit:preventsshiftingthetransmissionfrom
forward-to-reverseorfromreverse-to-forwardiftransmissionoutput
speedorthrottlepercentageispresent.RockingoutbyshiftingfromD
(Drive)toR(Reverse)andR(Reverse)toD(Drive)isstillavailableto
theoperatorprovidedtheseparametersarebelowthelimitallowed
forrockingoutthevehicle.
NOTE:Iftheelevatedoutputspeedorthrottlepositiondropsbelow
theinhibitthresholdwithinaspeciedgraceperiodof3seconds,the
inhibitwillself-clearandtherequestedshiftwillbecommanded.
NOTE:TheashingoftheSELECTrangeindicatesarequestedshift
iseithertemporarilyorpermanentlyinhibited.Theinhibitmayclearif
thecauseoftheinhibitclearswithin3secondsoftheshiftrequest.
Otherwise,theoperatormustre-selectthedesiredrange.
InhibitRollingDirectionChanges:Thisoptionalfeatureinhibits
forward/reversedirectionalchangeshiftsunlesstheoutputshaftspeedis
nearlystopped.TheTCMwillindicatethattheshiftisinhibitedbyashingthe
rangeSELECTdigitontheshiftselector.Iftheelevatedoutputspeedor
throttlepositiondropsbelowtheinhibitthresholdwithinaspeciedgrace
periodof3seconds,theinhibitwillself-clearandtherequestedshiftwillbe
commanded.
NOTE:Thisfeatureistypicallyusedinvehiclesthataregeared
forrelativelylowroadspeed,suchasstreetsweepersanddock
spotters.Thisoptionalfeaturemustbespeciedwhendeningthe
TCMcalibration.
ShiftsfromN(Neutral)toD(Drive)orN(Neutral)toR(Reverse)arealso
inhibitedwhentheTCMhasbeenprogrammed(byinput/outputfunction)
todetectthatauxiliaryequipmentisinoperationandtheshiftshouldnot
beallowed.
NOTE:Ifthecontrolshavesetadiagnosticcodethatholdsthe
transmissioninthecurrentrange,theSELECTdisplayontheshift
selectorwillbeblank.TheMONITORdisplaywillindicatetherange
inwhichthetransmissionislocked.TheCHECKTRANSindicator
willalsobeactivated.
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Allison Transmission T 270 Specifications

General

Brand	Allison Transmission
Model	T 270
Category	Controller
Language	English