DK40SE HST - neutral safety switch problem

[MotorSeven]

From the moved thread;

Went to put hay out this AM and tractor would not start. Glow plugs, all dash lights and all other lights work, battery is 2 months new. I suspect the neutral safety switch because I had to do the jiggle routine a while back. I sprayed some brake cleaner down onto the switch shaft and jiggled for about 5 min, then it started in Medium Range(not Neutral). Off to town to see if my dealer has one. So it looks like the easiest way to change it will be to remove the seat/pan?

from Koua;

"You do know that the "switch" is not a switch, it is a Potentiometer on the Hydro model. with 5 volts coming out of the cruise unit to one side of the 2000 ohm pot the other side to ground, and the slider of the pot goes back to the cruise unit, that detect its position by the voltage being fed back to the cruise unit from the slider (center wiper) of the pot. "

This is the switch that is on the shifter for Low, Medium & High range, so it this the one you are talking about? There is another one on the pedals that I assume would be tied to the cruise control.

My dealer had quite a time looking this part up since Kioti does not call it a neutral safety switch and the illustrations don't show the shifter lever at all. I am headed down to the quonset now to go over the shop manual which I should have done first, but we had 4" of rain last night and the pastures are under water again so I got sidetracked.

 

[murphy1244]

The one on the pedal is for the cruise. Maybe item 20 on this OEM Parts

 

[MotorSeven]

This one is straight down on the left hand of the drivers seat behind the fender well. It is round like a small hockey puck and has a shaft going through it that goes through the shifter lever at it's apex. There is also a pigtail with a square plug going to the wiring harness.

I am headed down there now to pull the seat/pan so I can get to it...................

 

[k0ua]

This one is straight down on the left hand of the drivers seat behind the fender well. It is round like a small hockey puck and has a shaft going through it that goes through the shifter lever at it's apex. There is also a pigtail with a square plug going to the wiring harness.

I am headed down there now to pull the seat/pan so I can get to it...................

That is the one, it is a POT. with the lever tied to the range shifter lever to move it thru its arc.. It is not a switch.. It also is the device that changes the dash lights from L to N to M to N to H based upon the voltage you select with the Potentiomenter as you move the lever thru its arc. Mine wont show the gear you are in when it gets below about 15 degrees.. I started it up at about 7 degrees this morning it started fine, but did not show the range until the tractor warmed up about 10 minutes. then it just pops on with whatever range you are in. I think the Cruise unit that this feeds may be just too cold to work right. I have seen this now about 3 or 4 times when I go operate in the extreme (for us) cold. Sorry I just got in from plowing the road and driveway.

 

[k0ua]

But I will say this, when my indicator light does not come on, the tractor will still start, in fact it will start in any range as well as Neutral. Which is not the same problem you have, but I believe they are related.. As soon as the tractor warms up, the light will come on, and the tractor will no longer start in gear, only one of the two N positions.

 

[k0ua]

You can check the POT with an ohmmeter, should be 2000 ohms between the outside legs, and of course variable ohms from the center to each end depending on where the pot slider is on its rotation.

You can watch an analog ohmmeter and see if there are any "dead" spots in the pot, or if the ohms are smooth thru its rotation. If you see any dropout "dead spots" then either try to clean it with some wd40 or replace it.. If you don't see any problem, my guess is it could be a temprature problem.. My problem as noted above is never manifest above freezing.

 

[MotorSeven]

It's called a "Range Shift Sensor", and you are correct it's on the Cruise Control circuit. After spraying it down it seems to be working, so I am going to order a new one(along with an extra ignition....just in case) before I take this one off. I will ohm test it before I remove it & I wonder if it is rebuildable/cleanable, or a sealed unit?

Also I was wrong it's not a puck with a straight shaft, it's a puck with a paddle arm that hooks to the linkage. I appreciate the info it helped me track it down a lot quicker.

 

[MotorSeven]

 

[murphy1244]

well, it worky?

 

[k0ua]

I love their measurement instructions 2000 ohms converted
I scratched my head on that one for a while, I guess they mean 2000 ohms variable.
Things just don't always translate from Korean all that well.

I don't know if it is sealed or not, I have never actually seen one, just the schematic and the pictorial diagram.

 

[MotorSeven]

Yeah I wonderd about that too. So it means that anything under 2000 means it's NG(no good)?

 

[k0ua]

Yeah I wonderd about that too. So it means that anything under 2000 means it's NG(no good)?

End to end it should be 2000 ohms. the center wiper/slider/moving arm of the pot should go from near zero to near 2000 when measured from an end to the center. Of course depending on which end you put the lead on will determine whether the resistance rises or falls as you move the wiper back and forth. Sort of a diagram below to illustrate what I am trying to say.

---^v^v---
|

well that didn't work

 

[k0ua]

Lets try this drawing

 

[MotorSeven]

I think I understand........thanks!!!

 

[MotorSeven]

The new one arrived, I pulled the seat pan(again, thank you Kioti for making that easy) and replaced the switch. They are sealed unit's and can't be taken apart and cleaned so I didn't even test the old one.

The new one was......{gasp}$123 and I see this as a silly redundant safety device. I mean, this is an HST, so unless you are dumb enough to leave the throttle up and step on one of the go pedals while trying to start it, then the tractor is not gonna move. Those people should have their tractor keys taken away from them, along with any other remotely sharp objects and handled by a large male nurse named "Clyde" for the rest of their years on this planet.
Before the new one arrived, the tractor had gotten to where it would only start in Medium range...kinda defeats the purpose of the switch eh???
So, if this fails again, I think Koua can tell me which wires to splice together to bypass the silly thing.......right James?

Old one:

 

[k0ua]

The new one arrived, I pulled the seat pan(again, thank you Kioti for making that easy) and replaced the switch. They are sealed unit's and can't be taken apart and cleaned so I didn't even test the old one.

The new one was......{gasp}$123 and I see this as a silly redundant safety device. I mean, this is an HST, so unless you are dumb enough to leave the throttle up and step on one of the go pedals while trying to start it, then the tractor is not gonna move. Those people should have their tractor keys taken away from them, along with any other remotely sharp objects and handled by a large male nurse named "Clyde" for the rest of their years on this planet.
Before the new one arrived, the tractor had gotten to where it would only start in Medium range...kinda defeats the purpose of the switch eh???
So, if this fails again, I think Koua can tell me which wires to splice together to bypass the silly thing.......right James?

Old one:

Not as simple as splicing wires, the module measures a voltage drop in the Potentiometer. 5 volts on the one outside lead and ground on the other, then the center lead will have a variable voltage on it depending on the arc of the lever. As you move the lever thru the "gears" L-N-M-N-H the changing voltage is read by the cruise module to determine what gear/range to display in the instrument panel and sends along a signal to allow the starter relay to pull up. To bypass this expensive part you would have to build a resistor network of 2 resistors and tap them in the center for the center lead. This would give you the voltage drop you would need to send a signal that the tractor was in neutral. Of course the N lamp would always be lit no matter which range you were in. I would need to look up the voltage that equals one of the N positions, as read by the module, and do the math to calculate the values of the resistors you would need to put together in your "network".. Clear as mud?

 

[k0ua]

The new one arrived, I pulled the seat pan(again, thank you Kioti for making that easy) and replaced the switch. They are sealed unit's and can't be taken apart and cleaned so I didn't even test the old one.

The new one was......{gasp}$123 and I see this as a silly redundant safety device. I mean, this is an HST, so unless you are dumb enough to leave the throttle up and step on one of the go pedals while trying to start it, then the tractor is not gonna move. Those people should have their tractor keys taken away from them, along with any other remotely sharp objects and handled by a large male nurse named "Clyde" for the rest of their years on this planet.
Before the new one arrived, the tractor had gotten to where it would only start in Medium range...kinda defeats the purpose of the switch eh???
So, if this fails again, I think Koua can tell me which wires to splice together to bypass the silly thing.......right James?

Old one:

Not as simple as splicing wires, the module measures a voltage drop in the Potentiometer. 5 volts on the one outside lead and ground on the other, then the center lead will have a variable voltage on it depending on the arc of the lever. As you move the lever thru the "gears" L-N-M-N-H the changing voltage is read by the cruise module to determine what gear/range to display in the instrument panel and sends along a signal to allow the starter relay to pull up. To bypass this expensive part you would have to build a resistor network of 2 resistors and tap them in the center for the center lead. This would give you the voltage drop you would need to send a signal that the tractor was in neutral. Of course the N lamp would always be lit no matter which range you were in. I would need to look up the voltage that equals one of the N positions, as read by the module, and do the math to calculate the values of the resistors you would need to put together in your "network".. Clear as mud?

 

[k0ua]

Did you get a chance to measure the pot. with an analog ohm meter as you slowly move it thru its arc? It should be smooth with no disconnections from the center pin to each end. A smooth scrolling variable resistance.

 

[rmorey]

I think paying $120 is way better than having to remember all that! :laughing:

 

[k0ua]

I think paying $120 is way better than having to remember all that! :laughing:

Elementary my dear Watson, Elementary!...

It would not be hard to build the bypass network, especially if you retained the plug on the old pot. You could easily cover it in the liquid rubber for waterproofing.