23S starter burned up, found the wire to the solenoid is always hot

JSum

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Looked for similar threads, but didn't find the exact information I was looking for.
I have a 2023 (I believe) new to me BX23S with just 33 hours on it. I have started and stopped it many times with no issue. yesterday after moving a trailer with it, I went to shut if off and it restarted twice. Even with the key out. I decided to move it to a different area so it wasn't blocking the garage. As I did, smoke started pouring out the side of the motor. I found that it was coming from the starter - now fried. I was able to buy a replacement starter, but decided to put the test light on the black/white spade wire and turn the key after reconnecting the battery. The test light was off and then turned on appropriately when I turned the key to start. The only problem is that the light stayed on indicating ongoing power to the wire even after I returned the key to the on position, turned it off and removed the key! I think that is why the starter burned up in the first place.

So, now my question is, how do I work this problem through? Is there a starter relay and if so where is it, or is it simply a faulty ignition switch? I have been searching and reading threads on here, searching the web, you tube and the WSM, but don't see a clear picture of where things are located and even what part to try to order. It raining out right now, but once it stops, I will go back out with fresh eyes and try to trace the wiring backwards from that point again and see if it makes more sense today....
 

JSum

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Update - had a quick break from rain so I was able to find the relays for the starter and headlights. I marked the starter relay and switched it with the headlight one and retested. I still have continuous power being delivered to the starter wire. Does that mean this is definitely a problem with the ignition itself? All the wires seem well protected and in the factory loom so I would think a short is less likely.
 

Blue2Orange

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Any local Kubota dealer? If so, shop and parts department should have an answer to your issues. There is a Limited Warranty Chart at the Kubota website. Maybe you have an issue covered by warranty.
 

Henro

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You have a test lamp, so you can check the output of the ignition switch that feeds the starter relay.

If you go to the sticky thread at the top of this sub forum, you will find an electrical diagram in post #13 that is the same as the BX23S.

It sure sounds like it is an ignition switch issue.

Edit: the sticky is titled Electrical Diagrams or something along those lines...
 
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JSum

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Any local Kubota dealer? If so, shop and parts department should have an answer to your issues. There is a Limited Warranty Chart at the Kubota website. Maybe you have an issue covered by warranty.
Several dealers, but I am not the original buyer. Talked to several parts people and they have helped out as much as possible.
 

JSum

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You have a test lamp, so you can check the output of the ignition switch that feeds the starter relay.

If you go to the sticky thread at the top of this sub forum, you will find an electrical diagram in post #13 that is the same as the BX23S.

It sure sounds like it is an ignition switch issue.

Edit: the sticky is titled Electrical Diagrams or something along those lines...
I had the same thought. Just got back from the dealer and put a new ignition switch in.
Same problem...... The wire going to the paddle connection that is on the starter is energized all the time. Its as if it is hot wired directly to the battery! I don't have a clue how that can be happening! Any malfunctioning safety sensors should PREVENT energy from going to that wire.
 

North Idaho Wolfman

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Several dealers, but I am not the original buyer. Talked to several parts people and they have helped out as much as possible.
The warranty follows the tractor not the owner, the warranty transferred to you when you bought it.
 

JSum

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UPDATE #2
I removed the starter relay completely and tested the wire that attaches to the starter solenoid and it STILL has power! Shouldn't it be dead? Its reading 12.4 volts. I can't figure out how this is still hot! The wiring diagrams in the WSM from Kubota books and from the electric subgroup #13 are blurry no matter how I try to zoom in on them and they quickly confuse me anyhow.
Starting to think I need to install the starter and just disconnect the wire once it fires up and load it on the trailer and haul it to the dealer.
I wonder if any of this would be covered under the warranty if it is even still under warranty. I'm the second owner and was told it was a 2023 machine. I imagine a dealer could run the serial number to see when it was put into service.
Anyone have some good insight to where I can look or what to try next?
 

Henro

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First, look at the PDF file of the wiring diagram that I referenced above. That way you can zoom in and it is clear!

Second, if you replaced the ignition switch with a new one, then chances are that the problem was not with the ignition switch. Perhaps you have a short in your wiring somewhere.

Connect your test light to the voltage point you question, then start moving wiring harnesses and stuff around and see if the light goes on and off. This would probably indicate that it’s a wiring issue.

Just a couple thoughts…

I would think the dealer could tell you whether the warranty is active or not if you gave them the serial number of the tractor. It might be worthwhile asking them before you take the tractor there and end up paying big bucks for something you could probably figure out yourself eventually.

Of course if money is not an issue, take it to the dealer, and relax!
 
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TheOldHokie

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windyridgefarm.us
I had the same thought. Just got back from the dealer and put a new ignition switch in.
Same problem...... The wire going to the paddle connection that is on the starter is energized all the time. Its as if it is hot wired directly to the battery! I don't have a clue how that can be happening! Any malfunctioning safety sensors should PREVENT energy from going to that wire.
Stuck/shorted starter relay?

Dan