Help with diagnosis please

ghost1

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Ferris IS 700Z. Got done mowing and turned off to use compressor to blow grass off machine. Got back on started it and now whenever any control is moved (steering handles, parking brake, pto), engine shuts off.
 

ILENGINE

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I suspect that you bumped something that is preventing the seat switch from sensing the operator in the seat. So could be that switch or a relay or harness that issue with that switch or relay.
 

ghost1

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I just bypassed seat switch, checked safety switches for steering arms and parking brake, and all are working as they should. Also checked continuity on whole mower using schematic with positive results. Noticed the starter relay was tied into safety switches and tested it also with multimeter. PTO switch also checking okay. I'm kinda running out of things to look at.
 

StarTech

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According the Schematic for 5901225 Ferris the seat switch is a NC (Normally Closed) swtich. This means when you are on the seat it is open so if you just jumper the switch connector you just told the mower no one is on the seat.
 

ghost1

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Thanks for replies. Tried both ways with seat switch, no difference.
 

ghost1

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Update: I think I may have found the issue. I've disconnected every switch in the system. Neutral switch (left and right), E brake switch, PTO, Ignition, connection to engine, seat switch, and I'm finding I have a short to ground on white wire circuit only. Is there a way to run this down? I connected multimeter using continuity and moved harness around to try to silence alarm on meter without luck.
 

ghost1

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Found problem. Connector from harness to seat switch has plug wrapped in a piece of wire that when pushed all way in connector rides on plastic creating open circuit that mower wants to run. It had backed out causing brown and white wire to connect thus sending path to ground. Owner had changed seats and wire was just hanging loose. Not sure how connector works but removed since owner doesn't want the safety of seat switch. This one has been a tough nut to crack.
 

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StarTech

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I wasn't sure if the Ferris mowers were using this shorting strip so I was waiting for someone else that knew for sure. I make a mental note that Ferris mowers are using this device.

I hate to say this but the operator is really taking a chance with the seat switch safety disabled. I personally I do not disable safeties as it is a liability issue and that I could get sued if someone got hurt because of a bypassed safety device.

IF you wish to enable it later use Stens 430-620 shorting connector.
 
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ghost1

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Thanks for that info Star Tech. I've never worked with a shorting connector. Are they a safety cut off if seat plug becomes detached?
 

StarTech

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Yes they short as if the seat switch contacts are closed. It came about because of operators disconnecting the seats and was having accidents. IT sorta like the customer here where a fly by night shop installed the wrong PTO safety switch. The guy was mowing his lawn when a limb knock him off the mower. The mower just keep on cutting grass until it hit the guy's wife new car. His insurance comany was after me because he had brought the mower to my shop after the accident. I had explain what cause the problem and that I had never worked on that mower before the accident. And my records proved it.
 
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