Electric Control Unit on a Grand L5030 HSTC

Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
Does anyone know where the Electric Control Unit is on my 2004 Grand L5030? I have a starting problem and my diesel mechanic wants to check for any codes. The tractor will not turn over. When you try to start it nothing happens. No click, no nothing. Everything else works as they should such as lights, fan, radio, dash lights... This happened late last winter but both of us have been to busy to check for the cause. He "thinks" it might be the main safely switch on the foot pedal. Of course this happened with 16" of new snow on the ground. So to keep my driveway and my customers driveways opened we hot wired it. He also had to cut a little bit of shaft off on the fuel soleniod. Now to start it I touch a wire from the starter to a bolt head and to turn it off I pull on a wire that is connected to the manual fuel shutoff lever on the fuel solenoid. We are hoping by looking at any codes it might give us a hint what the problem is.
 

TheOldHokie

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Does anyone know where the Electric Control Unit is on my 2004 Grand L5030? I have a starting problem and my diesel mechanic wants to check for any codes. The tractor will not turn over. When you try to start it nothing happens. No click, no nothing. Everything else works as they should such as lights, fan, radio, dash lights... This happened late last winter but both of us have been to busy to check for the cause. He "thinks" it might be the main safely switch on the foot pedal. Of course this happened with 16" of new snow on the ground. So to keep my driveway and my customers driveways opened we hot wired it. He also had to cut a little bit of shaft off on the fuel soleniod. Now to start it I touch a wire from the starter to a bolt head and to turn it off I pull on a wire that is connected to the manual fuel shutoff lever on the fuel solenoid. We are hoping by looking at any codes it might give us a hint what the problem is.
How does your mechanic pull codes from a Kubota tractor? That requires a scan tool plugged into a diagnostic port.

Does that tractor even have an ECU? If it dies the WSM should have the info you are looking for. You might even be able to display codes on the instrument panel.

Dan
 

Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
How does your mechanic pull codes from a Kubota tractor? That requires a scan tool pluggedport is. into a diagnostic port.

Does that tractor even have an ECU? If it dies the WSM should have not say where it isthe info you are looking for. You might even be able to display codes on the instrument panel.

Dan
He has a scanner. And, yes the WSM shows it has a ECU, however, it does not say where it is. That is why I did the post. We looked and cannot find the diagnostic port.
 

RCW

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Thank you, Lug66!! I will check that out in the morning. Hopefully it is at that location. Where did you find the screenshots?
Look at Kubota USA. There’s a section that has parts diagrams with part numbers.

Unfortunately I don’t have the link saved on my cell phone.

Edit --- here it is:

 
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Lug66

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Thank you, Lug66!! I will check that out in the morning. Hopefully it is at that location. Where did you find the screenshots?
The website (Kubota and Messicks) is located at the top of each picture. The left one has exact spot, B10402, in the Electrical section at Kubotas site. I figured you’d recognize that panel for the levers.
 

BAP

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I would be finding yourself a new diesel mechanic. If he needs to be able to plug a scanner in to look for codes in order to be able to see if the safety switches work, then he doesn’t know what he is doing. Safety switches can be tested with a meter and bypassed easily with a piece of wire to check that is the source of the problem. No need to hot wire the tractor or cut off part of the fuel solenoid shaft. You most likely have a safety switch issue or a starting solenoid problem.
 

GreensvilleJay

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1st step, locate and print out the 'wiring diagram' !! It'll be in the WSM, which www.Kubotabooks.com may have online for you to freely download

2nd step, examine all the wiring, and 'follow the volts' from battery to starter solenoid. usually 2-3-4 'safety' switches in series, any of which can stop power getting through.

Seems like this is a 20 year old tractor so odds are one of them is kaput. The 'fun' is physically getting to them to test or replace. it'd probably be worthwhile to just replace all of them, typically a $10 item ?
 

TheOldHokie

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Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
I would be finding yourself a new diesel mechanic. If he needs to be able to plug a scanner in to look for codes in order to be able to see if the safety switches work, then he doesn’t know what he is doing. Safety switches can be tested with a meter and bypassed easily with a piece of wire to check that is the source of the problem. No need to hot wire the tractor or cut off part of the fuel solenoid shaft. You most likely have a safety switch issue or a starting solenoid problem.
As I said in my first post this happened in the middle of winter with 16" of new snow on the ground at 9:00pm, with more snow called for later that night . No nice dry heated shop to work in. Just outside in the cold, the dark and snow working by flashlights. I had to get the tractor running to get my customers driveways opened. Without Doug I would have been screwed and most likely lose some customers who I could not afford to lose. I not sorry for what he did. A new fuel solenoid did not cost much and will not take long to install. Again, as I said in my first post he/we "think" it might be a safety switch issue. He just wants to cover all the possibles.
 
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Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
1st step, locate and print out the 'wiring diagram' !! It'll be in the WSM, which www.Kubotabooks.com may have online for you to freely download

2nd step, examine all the wiring, and 'follow the volts' from battery to starter solenoid. usually 2-3-4 'safety' switches in series, any of which can stop power getting through.

Seems like this is a 20 year old tractor so odds are one of them is kaput. The 'fun' is physically getting to them to test or replace. it'd probably be worthwhile to just replace all of them, typically a $10 item ?
I think your right. Might just replace the safety switches.
 

Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
What is the easiest way to test the safety switches? So far in the WSM I have found the seat, pto, foot pedal and clutch safety switches. Messick's has them but at a $200.00 price tag! If it is a switch gone bad I'd like to only replace it at this time. Still have to take a look at testing the starter solenoid see if it is good.
 

whitetiger

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Nov 20, 2011
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He has a scanner. And, yes the WSM shows it has a ECU, however, it does not say where it is. That is why I did the post. We looked and cannot find the diagnostic port.
There is no ECU on the hydro version, only on the GST version. You will not find a diagnostic port either, there isn't one.
It's a very basic system, with a few switches, and an instrument cluster that displays any error codes.
I am surprised that your tech can not read the very simple electrical schematic and the large color pictures of each electrical component and switch shown in their location in the WSM.
 

Jayhawk238

Member

Equipment
2004 L5030 HST/CAB
Oct 30, 2010
97
10
8
74
Featherville, ID, United States
There is no ECU on the hydro version, only on the GST version. You will not find a diagnostic port either, there isn't one.
It's a very basic system, with a few switches, and an instrument cluster that displays any error codes.
I am surprised that your tech can not read the very simple electrical schematic and the large color pictures of each electrical component and switch shown in their location in the WSM.
That was my bad. I am the one that missed its on GST models only. Also, mine must be old. No color pictures, only black & white.
 
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