85 engine electrical.pdf - Vintage Snow

Fuse LinkENGINE ELECTRICALPower Up Component TestingThe fuse link is the circuit protection device in Type Iand 1991-1992 Type II electrical system. Should asystem overload such as a dead short occur, the fusewire will open the circuit preventing further damage. Ifthis link should open, find and correct the problem andthen replace the fuse link. Never attempt to replacethe fuse link with a conventional fuse. Use only anOEM fuse link.cService of the fuse link is limited to verification ofwhether or not the wire is continuous. Remove fuselink from machine and use an ohmmeter to determineresistance value of wire between plugs. Resistancevalues of less than .5 ohms indicate a good wire.Values greater than that will necessitate linkreplacement. Current models will use a self settingcircuit breaker.Relay CoilscThe system relay coils are mounted on the front sideof the right footrest assembly on Type I and1991 -1992 Type II systems. The relays for latermodel Type II systems are mounted on the ECU.Their function is to control a major current carryingcircuit with a smaller, low current carrying controlcircuit. When the ECU or ignition switch closes thelow current poil circuit within the relay, the magnetismin the coil cI ~ ses the contact pOints, allowing current topass through the relay and power up to the ECU, fuelpump, etc. Both system types incorporate two bluerelays, one I ontrolling the fuel pump and the other theself shut-off time delay relay. The Type I system alsouses a bro n relay to control the main power input tothe ECU. n 1993 and later model Type II systems,the relays a e black.BLUEBROWNService to relays is limited to measuring pull-in coilresistance and measuring volt drop across contacts.The coil resistance should be between 65 and 70ohms measured between the two pins marked coil onrelay base. When relay is energized, volt drop acrossrelay contacts should be less than .1 vDC, measuredin parallel with relay. On the bench, the relay can bechecked by hooking the marked relay coil terminals toa 12v battery and checking resistance of relaycontacts. The resistance must be less than .2 ohms.o1993 and later Type II style EFI relays are tested byplacing 12 volts to contact left side as shown in thediagram to the right. Measuring volt drop acrosscontacts .1 vDC. Measure resistance of right sidecontact. This should be 100 ohms ± 10%.LeftRight100ohms±10%Bottom4.418/94