Service Manual

Piston(Traction)PumpControlSolenoidCoils
FRONT
RIGHT
1
2
3
g276032
Figure224
1.Pistonpump3.Reversesolenoidcoil
2.Forwardsolenoidcoil
Thepiston(traction)pumpusesanelectroniccontrolassemblyforswashplate
rotation.ElectricaloutputsfromthemachineTECcontrollerareprovidedto
two(2)solenoidcoilsforpumpcontrol.Thepistonpumpcontrolassemblyis
attachedtotheleftsideofthepistonpump(Figure224).
Note:Toassistintroubleshooting,thepistonpumpsolenoidcoilscanbe
exchangedbecausetheyareidentical.Iftheproblemfollowstheexchanged
coil,aproblemwiththecoillikelyexists.Iftheproblemremainsunchanged,
somethingotherthanthesolenoidcoilistheproblemsource(e.g.tractionpedal,
circuitwiring,hydraulicproblem).
SolenoidCoilTesting
1.Parkmachineonalevelsurface,lowercuttingdecks,stopengine,engage
parkingbrakeandremovekeyfromtheignitionswitch.
2.Locatepistonpumpsolenoidcoiltobetested(Figure224).Disconnectwire
harnessconnectorfromsolenoidcoil.
Note:Priortotakingsmallresistancereadingswithadigitalmultimeter,short
themetertestleadstogether.Themeterwilldisplayasmallresistancevalue
(usually0.5ohmsorless).Thisresistanceisduetotheinternalresistanceof
themeterandtestleads.Subtractthisvaluefromfromthemeasuredvalue
ofthecomponentyouaretesting.
ElectricalSystem:ComponentTesting
Page6–68
Groundsmaster
®
4000-D&4010-D
13202SLRevF