Jacobsen AR3 shuts of when key is returned to run position

[Drewtx]

Hey guys,
I'm new here and looking for some help diagnosing an issue with my 2014 Jacobsen AR3 mower and has a kubota D1105. The mower starts up and runs perfectly with the fuel shut off solenoid removed. I've eliminated it being any safety switches, replaced all the fuses, relays, replaced ignition switch and bench tested the solenoid to make sure it was working correctly. I've tested the plug going to the solenoid and it gets voltage when trying to start but all voltage drops off as soon as the key is returned to the run position so it seem that I'm not getting any power to hold the solenoid open. I know this isnt a tractor but thought this would be a good place to look for help since this mower has a kubota and any help will be greatly appreciated.

Thanks
Drew

 

[North Idaho Wolfman]

I would suggest getting ahold of the wiring diagram for the unit, as it's not a kubota thing.

It sounds like you have a dual coil solenoid, one coil pulls it in and the second coil holds it in.

Did you test the hold coil?

Your going to need to find the relay, fuse or wiring issue that is not letting the solenoid get the hold signal.

 

[Drewtx]

Hey Wolfman,

I do have the wiring diagram but its pretty confusing to follow. It does show that the two wires that power the solenoid trace back to a diode module. So worst case I'll have to try and trace them to wherever this diode module is.

You are correct. It is a dual coil solenoid and I tested the pull and hold on the solenoid. I tested the hold by just swapping the wires and pushing the plunger down and making contact and the plunger does hold in place. However it held with 12 volts applied and I only get about 4 volts from the connection that goes to the solenoid when the engine is running. When I start the engine the volts jump pretty high and then once the engine is running the slowly start to fall and settle to around 4.7 volts at the pigtail. Let me know if that sounds right but I'm no expert at this.

I have replaced the start relay already. I went ahead and just ordered a new solenoid but I'm still unsure that is the issue. I'm just a little stumped because the mower runs great with the solenoid pulled and everything operates as it should. It's just that the solenoid wont hold open once the engine fires up. I really appreciate your help. This is a kinda a rare machine so not a lot of info out there on this issue.

Drew

 

[Dave_eng]

I am going to send you a private message with my email address.

Send me a large photo or scan of the wiring diagram. Something I can make out.

Do you have the owners' manual?

It seems unusual that the hold in voltage in so low.

The difference between the hold and pull in parts of the solenoid have to do with the number of winding's of each coil and not the voltage they see.

I think there must be a safety system on your machine which is more electronic than a collection of safety switches in series. Kubota would call it an Operator Presence Controller (OPC).

This may be the defective component as its job would be to stop the engine if for example you fell off.

Dave

 

[greenacresnorth]

not knowing what exact machine you have, if its the 3 wheeled machine it looks like the hold power comes through the fuel pump internal relay. My question is if this is the same machine then is your fuel pump running? if its not then there is your problem. if it is then check connections at the fuel pump and ensure the white wire coming off the pump to the shut off coil has a good connection.

 

[North Idaho Wolfman]

Hey Wolfman,

I do have the wiring diagram but its pretty confusing to follow. It does show that the two wires that power the solenoid trace back to a diode module. So worst case I'll have to try and trace them to wherever this diode module is.

You are correct. It is a dual coil solenoid and I tested the pull and hold on the solenoid. I tested the hold by just swapping the wires and pushing the plunger down and making contact and the plunger does hold in place. However it held with 12 volts applied and I only get about 4 volts from the connection that goes to the solenoid when the engine is running. When I start the engine the volts jump pretty high and then once the engine is running the slowly start to fall and settle to around 4.7 volts at the pigtail. Let me know if that sounds right but I'm no expert at this.

I have replaced the start relay already. I went ahead and just ordered a new solenoid but I'm still unsure that is the issue. I'm just a little stumped because the mower runs great with the solenoid pulled and everything operates as it should. It's just that the solenoid wont hold open once the engine fires up. I really appreciate your help. This is a kinda a rare machine so not a lot of info out there on this issue.

Drew

Yes the diode module being defective will do exactly what your saying it's doing.

 

[Dave_eng]

Here is a post by a tractor owner who was getting low voltage to his stop solenoid. Something for you to check out since you reported low voltage to the hold coil. His system works the opposite of yours (power to shut down engine rather than power to keep it running)

I also have a recently acquired L4310 that would not shut off with the key about a month after owning it. I was not getting 12v out to the solenoid when the key was turned off. The relay was ok as well. I had read this thread about the fuse, so I started investigating that as another possibility. My fuses were all fine, BUT I happened to notice a bit of white corrosion on the black plastic around the bottom fuse holder.

Turns out it was not the fuse, but rather the fuse receptacle holder in the fuse box. The power wires are crimped onto these receptacles from the backside. The receptacles have spring tabs that make contact with the fuse legs. One side of the fuse receptacle was missing these spring tabs, it had corroded to the point of falling off. No contact on that side of the fuse, no 12v being sent out to the shut off relay.

Dave

 

[Drewtx]

not knowing what exact machine you have, if its the 3 wheeled machine it looks like the hold power comes through the fuel pump internal relay. My question is if this is the same machine then is your fuel pump running? if its not then there is your problem. if it is then check connections at the fuel pump and ensure the white wire coming off the pump to the shut off coil has a good connection.

Hey Mike,

That schematic looks like it's for the Jacobsen AR321 model. My model is just the AR3. The AR321 is similar to my model but I believe is a little more complex model as far as the electrical system goes and I believe will even have a LCD screen that will offer onboarding diagnostics. They make 3 models in this series of mowers. Mine being the basic AR3 model, then the AR321 and a AR331 being the top tier model. However my fuel pump is running and can hear the pump running when I turn the ignition switch to on and the engine does start and run fine with the solenoid removed from the machine. I will need to find that same schematic you attached for my model as that schematic should be very helpful. Thanks a bunch for your help and posting that schematic.

Drew

 

[Drewtx]

Here is a post by a tractor owner who was getting low voltage to his stop solenoid. Something for you to check out since you reported low voltage to the hold coil. His system works the opposite of yours (power to shut down engine rather than power to keep it running)

I also have a recently acquired L4310 that would not shut off with the key about a month after owning it. I was not getting 12v out to the solenoid when the key was turned off. The relay was ok as well. I had read this thread about the fuse, so I started investigating that as another possibility. My fuses were all fine, BUT I happened to notice a bit of white corrosion on the black plastic around the bottom fuse holder.

Turns out it was not the fuse, but rather the fuse receptacle holder in the fuse box. The power wires are crimped onto these receptacles from the backside. The receptacles have spring tabs that make contact with the fuse legs. One side of the fuse receptacle was missing these spring tabs, it had corroded to the point of falling off. No contact on that side of the fuse, no 12v being sent out to the shut off relay.

Dave

Hey Dave,

This is really good info and something I will look into today. I will go through the fuse panel and clean up all of the connections the best I can. This definitely sounds like a similar issue to what I'm experiencing. This is probably something I should have done before I started throwing new parts at this machine. I appreciate the help I've received from this forum. I will definitely update if I figure something out. Thanks again

Drew

 

[Drewtx]

Well it looks like I figured out the issue. Turns out that there was a switch on the brake release valve that had a corroded connection that was part of the circuit that provides power to the fuel shut off solenoid. The connection is still in pretty bad shape and will need to be replaced but was able to get it cleaned up in the meantime to make a good connection. Turns out this is the only switch on the machine that will allow the engine to try and start if the circuit is broken. All of the other switches wont even allow the the engine to try and crank over if when their circuits are broken. Anyways I just wanted to update incase someone else comes across a similar issue. I definitely wouldn't have figured it out if you guys didnt point me into the right direction. Thank you guys for all of help.

Drew

 

[Dave_eng]

Well it looks like I figured out the issue. Turns out that there was a switch on the brake release valve that had a corroded connection that was part of the circuit that provides power to the fuel shut off solenoid. The connection is still in pretty bad shape and will need to be replaced but was able to get it cleaned up in the meantime to make a good connection. Turns out this is the only switch on the machine that will allow the engine to try and start if the circuit is broken. All of the other switches wont even allow the the engine to try and crank over if when their circuits are broken. Anyways I just wanted to update incase someone else comes across a similar issue. I definitely wouldn't have figured it out if you guys didnt point me into the right direction. Thank you guys for all of help.

Drew

Thanks for coming back to give the final chapter. It helps everyone in the future.

Dave