got some elec. gremlins (seat switch,brake switch,pto switch) again this mowing season. i'm not that well versed in elec. problems but i manage to solve them eventually. would like to know if i'm on the right track to test the starter relay. relay has one red wire to it and i hooked my bump starter switch one end to the + battery and the other to the red relay wire to see if i could hot wire it to see if the started relay was any good. pushed the button and nothing. tapped it with a small hammer and still nothing. had about 10 volts going to that red wire in another test. pto would stop and then stare again when i wiggled the connecting wire. these are old mowers and those are the worst problems i have had. cleaned everything up last year and worked fine till last week then the same gremlins. ign switch seems good but i'm not the best when it comes to testing them. will check all the switches for corrosion this week and apply die-electric grease to the terminals. pto is rebuilt and worked great. reason for the started check is because nothing worked when i tried to start it and there is 12:20 volts at the battery. any ideas? thanks, Denny
ok i'm going to zero in on one wire at a time. i'm going to check the seat switch and the brake switch. seat first. i am not very good at the ohm testing so i hope someone on here can guide me in the right direction. will do the pto later. here is what i'm getting with my multimeter on the seat switch. btw its a yt6800. seat wires are red,blue and black coming from the switch and snap into black, gray, and yellow coming from the connector under the black try under the seat. with my multimeter set on ohm's and the red prong in the red wire slot and the black prong in the black slot i get a closed circuit. pushing on the small metal bar on the switch i get an open circuit. red on blue shows open when pushing bar down or up.blue on black shows open and closed when lever is pushed down. i don't remember this mower shutting off when running as i got off the mower to pick up yard stuff, it kept running. btw this started when the pto stopped working (it's about a year since new) and i shut her off and would not even turn over again. hot wired the starter and it works good.had electrical problems in the past but solved them by cleaning most terminals. any advice? thanks Denny
cleaned all the switches and connections and solved most of my problems but one and it's been a pain off and on for a couple years. it's the pto. when i flip pto switch the engine stops. so i disconnected the connection at the pto lines and flipped the switch and the engine stopped. jumped the pto with my bump start switch and i could hear it engage.underneath.that tells me the pto is good (only has about one season since new). green wire goes to the pto switch and the black to ign. switch. not very good at checking with an ohm meter on these switches. i have seen on this site where this has been a problem with some of the members here. any cure??? Denny
thank you very much for your reply yamadog. i always though there was something weird about that seat switch because in the past i would get off the seat to pickup stuff in the yard and the engine would stay running. only one time it shut off and i thought that was weird. looks like i'll have to modify an aftermarket seat switch because getting a factory yamaha switch is going to be impossible. i'll keep this mower running as long as i can.
update. i jumped the black wire and blue wire on the seat switch and when i turned the pto on i heard it start then the engine shut off. did a voltage check with engine running and got 11.99. i don't think thats enough to run the engine and pto. battery date is 1/2018. charging the batt. now and will start again wednesday. battery should not be bad with just 2 years on it but you know how that goes.yamadog,looks like i'll have to suck it up and get that seat switch. pto did not engage without jumping the blue and black. did engage when jumped for a second before the engine shut off. hate to just through parts at it but thats all i have for now. seat switch is black,blue and red. think it still sounds like a seat switch?? Denny
#2 update. i charged the battery and got 12.26 volts then spliced the blue and black wires together (soldered them) on the seat switch. everything is back to normal again and works good. pto fired right up. i'm ready for the next go around. i just think these yamaha lawn tractors are the bomb and like i told my wife i'll try to keep it going as long as i can. i have a tool and die and machinest life long friend who likes to mess with machinery so it looks like i might take this yamaha to the end. sorry about the spelling but i'm in a hurry today. Denny