BX25D not starting by key

[koja]

Hello everyone . I think I may have a bad key switch . The tractor is a 2014 BX25D with 340hrs. When I turn the key on everything comes to life as it should . But when I try to start it does nothing . It acted funny a couple of times in the last few months . What would happen then was i would turn the key to start and no start,, but as i would back off on the key,, it would start .Ok , I know , safety switch ? All of the switches work as they should . Checked them all ,the way the owners manual says ,after jumping the starter . So,,, took the key switch out and checked for continuity between the power terminal and the other three and they all checked out ! So now I'm thinking maybe the switch is ok ? It is almost impossible to check with it hooked up because of the location of it under the dash . So I checked on the starter itself (see picture) . On the big lug with the red boot I have 12.89 volts (not running) at all times . Now ,, the black wire above the red lug (that's where I jumped it to start it) has no power with key off as it should . But turn the key to run,,, and I have 10.86 volts . Weird . Turn the key to start and drops a little to 10.2 volts . My thinking is that black wire should have no voltage till the key is turned to start, right? When I jumped the starter the tractor worked as it should . My dealer is thirty miles away , but talked to them the other day and they ordered a new switch . Just not 100% sure its the switch now . That black wire having voltage makes me think the switch is bleeding over some current .

 

[Grouse Feathers]

It sounds like you may have a wiring problem instead of a switch problem. I have a BX2370 and I downloaded the WSM for the BXxx60 tractors as I believe they are nearly identical. The wiring WDs look to be identical and I suspect the BX25D have the same wiring. The BXxx60 WSM is available for free and may help your troubleshooting at: http://kubotabooks.com/AutoIndex/index.php?dir=Tractor Owners Manuals/

 

[koja]

Hello everyone . I think I may have a bad key switch . The tractor is a 2014 BX25D with 340hrs. When I turn the key on everything comes to life as it should . But when I try to start it does nothing . It acted funny a couple of times in the last few months . What would happen then was i would turn the key to start and no start,, but as i would back off on the key,, it would start .Ok , I know , safety switch ? All of the switches work as they should . Checked them all ,the way the owners manual says ,after jumping the starter . So,,, took the key switch out and checked for continuity between the power terminal and the other three and they all checked out ! So now I'm thinking maybe the switch is ok ? It is almost impossible to check with it hooked up because of the location of it under the dash . So I checked on the starter itself (see picture) . On the big lug with the red boot I have 12.89 volts (not running) at all times . Now ,, the black wire above the red lug (that's where I jumped it to start it) has no power with key off as it should . But turn the key to run,,, and I have 10.86 volts . Weird . Turn the key to start and drops a little to 10.2 volts . My thinking is that black wire should have no voltage till the key is turned to start, right? When I jumped the starter the tractor worked as it should . My dealer is thirty miles away , but talked to them the other day and they ordered a new switch . Just not 100% sure its the switch now . That black wire having voltage makes me think the switch is bleeding over some current .

 

[bxray]

Here is the wiring diagram for bx25d.
The circuit is simple.
Should see power from start switch to pto safety switch, then hst safety switch.
Then on to the starter.

Ray

 

[kubotasam]

When you checked the switch for continuity did you measure the resistance between the terminals or just check for continuity. You have resistance in that start circuit causing a voltage drop. The switch can show continuity but still have enough internal corrosion to cause the voltage drop. The same problem can occur in any of the safety switches in the circuit. THey all should read 0 ohms when closed.
You do not have enough current to activate the starter solenoid.
A fix that many have used is to install a separate relay next to the starter solenoid. Get power directly from the large terminal on the starter run through a fuse then to your new relay, then to the small terminal on the starter. Use the original small wire from the starter (that comes from the switch) as the switching current on the new relay.
This eliminates all places of high resistance but still keeps the safety switches active.

 

[koja]

To begin with , thank you whoever fixed my double post . Thank you Ray for the wiring diagram. Looked all over the internet for that . And no kubotasam , I only checked for continuity . But I will check as you suggested . Thanks all .

 

[bxray]

Hi Koja,

Yes, Ohm out the switches, check the wire connectors as well.

You could disconnect the battery and ohm out from pto switch to the starter to see if the circuit is good from that point.

If you can begin from the starter switch that would help.

With the battery disconnected you can start from the pos battery lead to the starter and turn the switch to start.


It should be well below .1 ohm.

For every .1 ohm at 10 amp it will drop 1 volt.
And if it is much higher than the starter resistance it will rob all the power.

The wiring diagram is only avalable from the wsm.
It is a good investment as it is packed with info.

Ray

 

[koja]

I tried finding a workshop manual online last night but had no luck . Tried a search on here also but couldn't find where I can get one . Will the dealer be ableto get for me ? If so do you have any idea of cost ?

 

[cerlawson]

Four years ago Messics charged $74 plus shipping for WSM..

 

[koja]

Four years ago Messics charged $74 plus shipping for WSM..

Sounds like money well spent . When I pick up the new key switch I think I'll try to order one from the dealer .

 

[koja]

It sounds like you may have a wiring problem instead of a switch problem. I have a BX2370 and I downloaded the WSM for the BXxx60 tractors as I believe they are nearly identical. The wiring WDs look to be identical and I suspect the BX25D have the same wiring. The BXxx60 WSM is available for free and may help your troubleshooting at: http://kubotabooks.com/AutoIndex/index.php?dir=Tractor Owners Manuals/

Thank you grouse feathers for the link .

 

[Mork]

Odds are the ignition switch is corroded. Take it apart and clean it.

 

[koja]

Well good news , she starts again! Thanks to you all . You all convinced me to check things out further with a multi meter . Turns out the HST safety switch was bad . The safety switch has four connectors/ wires . One side of the switch worked fine . Continuity and .09 ohms . The other side/wires , nothing . That must be why I was getting some voltage at the start wire on the starter . I would have argued all day that it was the key switch (and would have been wrong) . But thanks to you all, you lead me in the right direction . I made up two jumper wires to bypass the safety switch for now . I will stop by the dealer tomorrow after work and get the bad one replaced . And boy what a pain that one is get to .
But again ,, thanks!!!

 

[Mork]

Well good news , she starts again! Thanks to you all . You all convinced me to check things out further with a multi meter . Turns out the HST safety switch was bad . The safety switch has four connectors/ wires . One side of the switch worked fine . Continuity and .09 ohms . The other side/wires , nothing . That must be why I was getting some voltage at the start wire on the starter . I would have argued all day that it was the key switch (and would have been wrong) . But thanks to you all, you lead me in the right direction . I made up two jumper wires to bypass the safety switch for now . I will stop by the dealer tomorrow after work and get the bad one replaced . And boy what a pain that one is get to .
But again ,, thanks!!!

Isn't this machine still under warranty?

 

[koja]

Yes Mork, still under warranty . Dealer is thirty miles away and I have no trailer . Rather than make it difficult I used a rainy Saturday , tracked the bad part down, stopping tonight after work at the dealer and picking up the replacement . Easier and more convenient for me and switch is no charge .