Toro Groundsmaster 4500-D Series - Piston (Traction) Pump Control Solenoid Coils

Piston(Traction)PumpControlSolenoidCoils
g309820
Figure216
1.Pistonpump3.Reversesolenoidcoil
2.Forwardsolenoidcoil
Thepiston(traction)pumpusesanelectroniccontrolassemblyforswashplate
rotation.ElectricaloutputsfromthemachineTECcontrollerareprovidedto
two(2)solenoidcoilsforpumpcontrol.Thepistonpumpcontrolassemblyis
attachedtotheleftsideofthepistonpump(Figure216).
Note:Toassistintroubleshooting,thepistonpumpsolenoidcoilscanbe
exchangedbecausetheyareidentical.Iftheproblemfollowstheexchanged
coil,aproblemwiththecoillikelyexists.Iftheproblemremainsunchanged,
somethingotherthanthesolenoidcoilistheproblemsource(e.g.tractionpedal,
circuitwiring,hydraulicproblem).
SolenoidCoilTesting
1.Parkmachineonalevelsurface,lowercuttingdecks,stopengine,engage
parkingbrakeandremovekeyfromtheignitionswitch.
2.Locatepistonpumpsolenoidcoiltobetested(Figure216).Disconnectwire
harnessconnectorfromsolenoidcoil.
Note:Priortotakingsmallresistancereadingswithadigitalmultimeter,short
themetertestleadstogether.Themeterwilldisplayasmallresistancevalue
(usually0.5ohmsorless).Thisresistanceisduetotheinternalresistance
ofthemeterandtestleads.Subtractthisvaluefromthemeasuredvalue
ofthecomponentyouaretesting.
ElectricalSystem:ComponentTesting
Page6–54
Groundsmaster
®
4500-D/4700-D
19245SLRevA