CDL COMBINATION VEHICLES QUESTIONS
WITH CORRECT ANSWERS 2025
WhenMshouldMyouMuseMtheMhandMvalveMtoMparkMaMcombinationMvehicle?M-MCORRECTMANSWER-
never
WhichManswerMisMcorrectMforMtheMairMvalvesMwhenMtestingMtheMtrailerMserviceMbrakesMonly?M-
MCORRECTMANSWER-
ServiceMBrake:Moff;MParkingMBrake:Moff;MTrailerMairMsupply:MinM/Mopen;MTrolly:Mapplied
YouMareMcouplingMaMsemiMtrailerMtoMyourMtractorMbutMhaveMnotMyetMbackedMunder.MTheMtrailerMisM
atMtheMrightMheightMwhen:M-MCORRECTMANSWER-
ItMwillMbeMraisedMslightlyMwhenMtheMtractorMisMbackedMunderMit.
HowMshouldMyouMtestMtheMtractorMtrailerMconnectionMforMsecurity?M-MCORRECTMANSWER-
PullMgentlyMforwardMinMlowMgearMagainstMtheMlockedMtrailerMbrakes,MthenMinspectMtheMcoupling
WhichManswerMisMcorrectMforMtheMairMvalvesMwhenMtestingMtheMtrailerMspring/parkingMbrakesMonl
y?M-MCORRECTMANSWER-
ServiceMBrake:Moff;MParkingMBrake:Moff;MTrailerMairMsupply:Mout;MTrolly:Mreleased
YourMemergencyMairMlineMbreaksMorMgetsMpulledMapartMwhileMyouMareMdriving.MTheMlossMofMpress
ureMwillMcauseMthe:M-MCORRECTMANSWER-EmergencyMtrailerMbrakesMtoMcomeMon
YouMsupplyMairMtoMtheMtrailerMtanksMby:M-MCORRECTMANSWER-
PushingMinMtheMtrailerMairMsupplyMvalve.
ThereMareMtwoMthingsMthatMaMdriverMcanMdoMtoMpreventMaMrollMover.MTheyMare:M(1)MkeepMtheMcarg
oMasMcloseMtoMtheMgroundMasMpossible;MandM(2):M-MCORRECTMANSWER-GoMslowlyMaroundMturns.
, YouMareMcouplingMaMsemiMtrailerMtoMyourMtractorMbutMhaveMnotMyetMbackedMunder.MTheMtrailerMisM
atMtheMrightMheightMwhen:M-MCORRECTMANSWER-
ItMwillMbeMraisedMslightlyMwhenMtheMtractorMisMbackedMunderMit.
TheMfifthMwheelMlockingMleverMisMnotMlockedMafterMtheMjawsMcloseMaroundMtheMkingpin;MthisMmea
n:M-MCORRECTMANSWER-
TheMcouplingMisMnotMrightMandMshouldMbeMfixedMbeforeMdrivingMtheMcoupledMunit
WhenMbackingMyourMtractorMunderMaMtrailer,MyouMshouldMexpect:M-MCORRECTMANSWER-
TrailerMwillMbeMliftedMslightlyMwhenMtheMtractorMbacksMunderMit.
BeforeMyouMstartMtoMuncouple,MyouMmustM-MCORRECTMANSWER-
MakeMsureMtheMgroundMisMsolidMandMcanMsupportMtheMweightMofMtheMtrailer
DuringMuncoupling,MyouMshouldMdisconnectMelectricalMcableMandM-MCORRECTMANSWER-
HangMitMwithMtheMplugMdown
AsMpartMofMyourMvehicleMinMinspectionMtest,MifMyourMvehicleMisMequippedMwithMairMbrakesMandMha
sMaMtrailer,MyouMwillMinspectMtheMairMconnectionsMbetweenMtheMtruckMorMtractorMandMtheMtrailer.M
MakeMsureMthatMtheM________MareMlockedMinMplaceMandMfreeMofMdamageMorMairMleaks.M-
MCORRECTMANSWER-GladMhands
IfMyourMvehicleMgetsMstuckMonMaMrailroadMtrack,MyouMshouldM-MCORRECTMANSWER-
GetMawayMfromMyourMvehicleMandMcallM911MorMtheMpostedMemergencyMnumber
IfMyourMtestMofMtheMtractorMprotectionMvalveMisMsuccessful,M-MCORRECTMANSWER-
TheMtractorMprotectionMvalveMcontrolM(trailerMairMsupplyMcontrol)MwillMpopMoutMorMgoMfromM"nor
mal"MtoM"emergency"
WITH CORRECT ANSWERS 2025
WhenMshouldMyouMuseMtheMhandMvalveMtoMparkMaMcombinationMvehicle?M-MCORRECTMANSWER-
never
WhichManswerMisMcorrectMforMtheMairMvalvesMwhenMtestingMtheMtrailerMserviceMbrakesMonly?M-
MCORRECTMANSWER-
ServiceMBrake:Moff;MParkingMBrake:Moff;MTrailerMairMsupply:MinM/Mopen;MTrolly:Mapplied
YouMareMcouplingMaMsemiMtrailerMtoMyourMtractorMbutMhaveMnotMyetMbackedMunder.MTheMtrailerMisM
atMtheMrightMheightMwhen:M-MCORRECTMANSWER-
ItMwillMbeMraisedMslightlyMwhenMtheMtractorMisMbackedMunderMit.
HowMshouldMyouMtestMtheMtractorMtrailerMconnectionMforMsecurity?M-MCORRECTMANSWER-
PullMgentlyMforwardMinMlowMgearMagainstMtheMlockedMtrailerMbrakes,MthenMinspectMtheMcoupling
WhichManswerMisMcorrectMforMtheMairMvalvesMwhenMtestingMtheMtrailerMspring/parkingMbrakesMonl
y?M-MCORRECTMANSWER-
ServiceMBrake:Moff;MParkingMBrake:Moff;MTrailerMairMsupply:Mout;MTrolly:Mreleased
YourMemergencyMairMlineMbreaksMorMgetsMpulledMapartMwhileMyouMareMdriving.MTheMlossMofMpress
ureMwillMcauseMthe:M-MCORRECTMANSWER-EmergencyMtrailerMbrakesMtoMcomeMon
YouMsupplyMairMtoMtheMtrailerMtanksMby:M-MCORRECTMANSWER-
PushingMinMtheMtrailerMairMsupplyMvalve.
ThereMareMtwoMthingsMthatMaMdriverMcanMdoMtoMpreventMaMrollMover.MTheyMare:M(1)MkeepMtheMcarg
oMasMcloseMtoMtheMgroundMasMpossible;MandM(2):M-MCORRECTMANSWER-GoMslowlyMaroundMturns.
, YouMareMcouplingMaMsemiMtrailerMtoMyourMtractorMbutMhaveMnotMyetMbackedMunder.MTheMtrailerMisM
atMtheMrightMheightMwhen:M-MCORRECTMANSWER-
ItMwillMbeMraisedMslightlyMwhenMtheMtractorMisMbackedMunderMit.
TheMfifthMwheelMlockingMleverMisMnotMlockedMafterMtheMjawsMcloseMaroundMtheMkingpin;MthisMmea
n:M-MCORRECTMANSWER-
TheMcouplingMisMnotMrightMandMshouldMbeMfixedMbeforeMdrivingMtheMcoupledMunit
WhenMbackingMyourMtractorMunderMaMtrailer,MyouMshouldMexpect:M-MCORRECTMANSWER-
TrailerMwillMbeMliftedMslightlyMwhenMtheMtractorMbacksMunderMit.
BeforeMyouMstartMtoMuncouple,MyouMmustM-MCORRECTMANSWER-
MakeMsureMtheMgroundMisMsolidMandMcanMsupportMtheMweightMofMtheMtrailer
DuringMuncoupling,MyouMshouldMdisconnectMelectricalMcableMandM-MCORRECTMANSWER-
HangMitMwithMtheMplugMdown
AsMpartMofMyourMvehicleMinMinspectionMtest,MifMyourMvehicleMisMequippedMwithMairMbrakesMandMha
sMaMtrailer,MyouMwillMinspectMtheMairMconnectionsMbetweenMtheMtruckMorMtractorMandMtheMtrailer.M
MakeMsureMthatMtheM________MareMlockedMinMplaceMandMfreeMofMdamageMorMairMleaks.M-
MCORRECTMANSWER-GladMhands
IfMyourMvehicleMgetsMstuckMonMaMrailroadMtrack,MyouMshouldM-MCORRECTMANSWER-
GetMawayMfromMyourMvehicleMandMcallM911MorMtheMpostedMemergencyMnumber
IfMyourMtestMofMtheMtractorMprotectionMvalveMisMsuccessful,M-MCORRECTMANSWER-
TheMtractorMprotectionMvalveMcontrolM(trailerMairMsupplyMcontrol)MwillMpopMoutMorMgoMfromM"nor
mal"MtoM"emergency"
