Toro Greensmaster 3120 - Page 210

IdentifyingtheRelaysandtheirFunctions(continued)
LowerRelay(K5)Whenenergizedbythesolidstatetimer,thelowerrelay
allowscurrentowtothehydraulicsolenoidvalvecoilsS2andS4causingthe
cuttingunitstolower.Thelowerrelayislocatedunderthecontrolpanelonthe
leftsideoftheoperatorseat.
RaiseRelay(K6)Whenenergizedbythejoystickraiseswitch,theraiserelay
allowscurrentowtohydraulicsolenoidvalvecoilsS2andS3causingthe
cuttingunitstoraise.Theraiserelayislocatedunderthecontrolpanelonthe
leftsideoftheoperatorseat.
BacklapRelay(K7)(machineswithbacklaponly)Thebacklaprelayisonly
installedonmachineswiththebacklapfeature.Therelayisenergizedbythe
backlapswitchwhenthebacklapleverisintheRposition.Thebacklaprelay
preventsthecuttingunitsfromengagingwhiletheengineiscrankingifthe
backlapleverisintheRposition.Thebacklaprelayislocatednearthefunctional
controllever.
ChargeCircuitRelay(K8)Thechargecircuitrelayisenergizedwhenthekey
switchisintheRunorStartposition.Thechargecircuitrelayallowsoutputfrom
theenginealternatortoreachthemachineelectricalcircuits.Thechargecircuit
relayislocatedunderthefrontoftheoperatorseat.
TestingtheRelays
1.Parkthemachineonalevelsurfaceandlowerthecuttingunits.Makesure
theengineisoffandthekeyswitchisintheOFFposition.
2.Removethecontrolpanelshield.
Note:Sincealloftherelaysusedonthemachineareidentical,usethetag
onthewireharnessattherelayconnectortohelplocatethedesiredrelay.
3.Locatetherelaytobetestedanddisconnectwireharnessconnectorfrom
therelay.Ifdesired,removetherelayfromthemachinefortesting.
4.Useamultimeter(ohmssetting)tomeasuretheresistancebetweenthe
followingrelayterminals;refertoFigure92.
A.Continuityshouldexistbetweenterminals87aand30.
B.Thereshouldnotbecontinuitybetweenterminals87and30.
C.Resistancebetweenterminals86and85(relaycoil)shouldbefrom80
to90ohms.
5.Connectamultimeter(ohmssetting)torelayterminals30and87.Ground
terminal86andapply+12VDCtoterminal85.Therelayshouldmakeand
breakcontinuitybetweenterminals30and87as12VDCisappliedand
removedfromterminal85.
6.Connectamultimeter(ohmssetting)torelayterminals30and87a.Ground
terminal86andapply+12VDCtoterminal85.Therelayshouldmakeand
breakcontinuitybetweenterminals30and87aas12VDCisappliedand
removedfromterminal85.
7.Replacetherelayifnecessary.
8.Iftherelaytestscorrectlyandacircuitproblemstillexists,checkthewire
harnesses;refertoAppendixA(pageA–1).
9.Ifpreviouslyremovedfortesting,installtherelayandconnectthewire
harnesstotherelay.
10.Installthecontrolpanelshieldbeforereturningthemachinetoservice.
ElectricalSystem:TestingtheElectricalComponents
Page5–24
Greensmaster3120
17230SLRevC