Operation
Toreleasetheparkingbrakeafteralow-pressureoccurrence,
rechargesystemtoatleast70psi(483kPa)andpushinthe
parkingbrakecontrol.Ifthesystemcannotberechargedand
thevehiclemustbemoved,thespringbrakemustbemanually
released(caged).
WARNING
Topreventpropertydamage,personalinjury,or
death:
•Alwaysinstallwheelchockswhenmanually
releasingtheparkingbrakes,orthevehiclecan
roll.
•Fortowing,makesurethevehicleissecurely
connectedtotowvehicleandtowvehicle
parkingbrakesareappliedbeforereleasingthe
disabledvehicle’sparkingbrakes.
•Toensurereleaseofparkingbrake,alwayscage
thespringinthebrakechamber.
•Undernocircumstancesshouldthespring
brakechamberbedisassembledforthepurpose
ofreleasingtheparkingbrake.
Intheeventitisnecessarytomovethevehicleafteran
emergencyapplication(beforeairpressurecanberestored),
theparkingspringcanbecompressedmechanicallytorelease
thebrake.Areleasestudspringcagingtoolisfurnishedwith
thebrakechamberassembly.Thereleasestudengagesinthe
springpressureplateanditsnutistightenedtocompress,cage
thespring,andreleasethebrake.
Removereleasestudassemblyfromcarryingpocket.
Applyalightcoatofantiseizetothethreadsofthereleasestudto
avoidanyunnecessarywearofthethreads.Removetheaccess
plugfromtheendofthespringchamber.Insertthereleasestud
throughtheopeninginthechamberandintothespringpressure
plate.
Turnthereleasestudone-quarterturntoengagethetangson
thereleasestudintotheslotinthepressureplate.Installthenut
onthereleasestud.Besuretangonreleasestudstaysengaged
withslotonpressureplatewhileinstallingthenut.Tightenthe
nutwithawrenchtocompressthespring.
ParkingBrakeReset
Chargespringbrakechamberswithairpressure.Loosennut
andremovethereleasestudandnutfromthespringhousingand
reinstalltheaccesspluginthechamberopening.Reinstallthe
releasestudandnutinthecarryingpocketonthebrakechamber
housing.
ParkingBrakeAlarm
Iftheparkingbrakealarmsounds(horncontinuouslyblows
whendriver’sdoorisopened),presstheservicebrakepedal.
Then,afterturningtheignitionswitchtotheONorACCposition,
makesurethattheparkingbrakeisset.Foramoredetailed
descriptionofthealarm,seetheParkingBrakeAlarminthe
Electricalsectionabove.
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