Toro Groundmaster Series - Diode Assemblies (Model 31902 and 31903)

DiodeAssemblies(Model31902and31903)
g305875
Figure102
(shownwithhydraulictankremoved)
1.Tractionpump
3.DiodeatconnectorP56(EGR)
2.DiodeatconnectorP57(starter)
Two(2)differentdiodesareusedontheGroundsmaster3300/3310(model
31902and31903)machines.Themaximumcurrentallowedthroughanyofthe
diodesis6amps.Thediodescanbeidentiedbytheirblackcoloranddiode
symbolontheendofthediodebody.Thediodesplugintothemainwireharness
ontherightsideframerailnearthetractionpump.
•Adiodeassembly(atmainwireharnessconnectorP57)isusedforcircuit
protectionfromvoltagespikesthatoccurwhenthestartersolenoidis
de−energized.
•Adiodeassembly(atmainwireharnessconnectorP56)isusedtoprotect
theengineECUfromreversepolarityintheEGRrelaycircuit.
TestingtheDiodeAssemblies
1.Parkthemachineonalevelsurface,lowerthecuttingunit(orattachment),
engagetheparkingbrake,setthekeyswitchtotheOFFpositionandremove
thekeyfromthekeyswitch.
2.Locateandremovethediodefromthewireharness.Checkthediodeand
thediodeholderfordamageorcorrosionandcleanorrepairifnecessary.
3.Useamultimetertocheckforvoltagedropacrossthediodeterminals(diode
testsetting).Contactthemultimeterred(+)leadtodiodeterminalAandthe
black(−)leadtodiodeterminalB.Areadingoflessthan0.7voltsshouldbe
displayedonthemultimeter.
OR
Usethetableprovidedandamultimeter(ohmssetting)tomeasurethe
resistanceacrossthediodeterminals.
Groundsmaster
®
3200,3300and3310
Page6–53
ElectricalSystem:TestingtheElectricalComponents
19240SLRevA