I appreciate all the advice, I tested the seat switch and it appeared to work without issue. I then shot the wires from the OPC back to the plug, the outside two checked, the center wire I assume is a ground? I could not get continuity between the center wire and anything on the plug of the OPC. I tried to test it against some bare metal and did not get continuity either.
B2650 5amp OPC/Panel keeps blowing
- Thread starter Pavedog
- Start date
Check the cable. You can use a 12V 55W bulb instead of the fuse. This way the bulb lights brightly when the fault is present but limiting the current to a safe value. All described in my earlier posts and links.
The other safety switches are connected to the same fuse, so you can check the other wiring too. Intermittent faults can be tricky to find, but this way makes it easy. If the bulb does not light you can run your tractor with it. When it stops and the bulb is lighting the fault is present again.
You had mentioned that the fuse blew when you put the seat down. So focus on that wiring first, look out for chafed parts. In my friends tractor the short was in the seat itself (seat switch to chassis short sometimes).
p.s.: do not measure resistance with a multimeter, can be misleading. You can measure voltages in the circuit, this has way more coverage.
The other safety switches are connected to the same fuse, so you can check the other wiring too. Intermittent faults can be tricky to find, but this way makes it easy. If the bulb does not light you can run your tractor with it. When it stops and the bulb is lighting the fault is present again.
You had mentioned that the fuse blew when you put the seat down. So focus on that wiring first, look out for chafed parts. In my friends tractor the short was in the seat itself (seat switch to chassis short sometimes).
p.s.: do not measure resistance with a multimeter, can be misleading. You can measure voltages in the circuit, this has way more coverage.
It was a bad seat switch afterall. It was causing a short. When I jumpered the seat switch connector the tractor ran, fuse did not blow and I could drive it. Thanks again for all the help. Just need to order a new switch 
I used the tractor last two days for mowing and when I got up this morning to finish the OPC fuse was blown again! I have gone through the wiring between the OPC and switches, no breaks or chaffs, all sealed and wrapped in flexible covering? I am really besides myself with this one.
If the switches and wiring are fine it has to be the OPC, or am I missing something?
If the switches and wiring are fine it has to be the OPC, or am I missing something?
GreensvilleJay
Well-known member
Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Your post #23 kinda rules out 'bad' OPC.
This is one of those 'need to see it, to fix it' problems. Have another pair of eyes check over the wiring, especially with you sitting in the seat. A wire might move juuuust enough to cause the short,without showing any 'real' damage.
This is one of those 'need to see it, to fix it' problems. Have another pair of eyes check over the wiring, especially with you sitting in the seat. A wire might move juuuust enough to cause the short,without showing any 'real' damage.
PHPaul
Well-known member
Equipment
B2650, Pronovost snow blower, Landpride rotary mower, Howard tiller, box blade
Yup, me too. Several times. I got tired of forking over $45 for replacements and jumpered it.
(Cue Safety Nazi Meltdown...)
I used a jumper on the seat switch to finish the mowing, however whenever I tried to set the parking break with the PTO disengaged it would burn out the OPC/Panel 5am fuse again.
I want to avoid just replacing parts, I have tested the seat wiring and it tested fine. I guess I will need to do the same with the neutral safety switch too
I want to avoid just replacing parts, I have tested the seat wiring and it tested fine. I guess I will need to do the same with the neutral safety switch too
whitetiger
Moderator
Staff member
Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Replace the HST safety switch; some fail, which causes an intermittent short that blows the fuse.
You could unplug the HST switch and jump the harness connector to verify it is causing the short.
You are right, do not swap out parts unless you have identified the fault. In case of my friends tractor this would have been an expensive and time consuming adventure, everything initially pointed to the shut off solenoid.
Or disconnect / jumper suspected switches for a while, as suggested by whitetiger.
Check out my suggestion earlier with replacing the fuse by a 12V bulb. I did that in my friends tractor who had the same problem and that we could not replicate while I was there.
But then he phoned me and said the tractor had stopped and the bulb was lighting, so the short present, and now he could move the wires until the bulb went dark again. He found the faulty wire straight away.
whitetiger
Moderator
Staff member
Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
The short that occurs in the HST safety switch is very intermittent and a quick short as the pedal is moved. You would have to watch the light bulb constantly and not blink.
You can also unplug the switch and connect an Ohm meter to it. The pedal can then be cycled back and forth while rattling the pedal while watching the meter. When it shorts for a brief moment, you will see the numbers jump. It happens so quickly that you probably will not be able to read the number.
This switch blowing the 5-amp fuse is a very common and well-known occurrence.
You can also unplug the switch and connect an Ohm meter to it. The pedal can then be cycled back and forth while rattling the pedal while watching the meter. When it shorts for a brief moment, you will see the numbers jump. It happens so quickly that you probably will not be able to read the number.
This switch blowing the 5-amp fuse is a very common and well-known occurrence.
dirtydeed
Well-known member
Lifetime Member
Equipment
B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
Ok, will check out the HST switch and see if it is possible to test it. What I don't get is when I try to put the new seat switch in it will blow the fuse every time, almost like the new switch is bad. If I jumper the seat switch it is good unless I try to set the parking break. All of these switches are in the circuit to the OPC.
I jumped the switch out and used the tractor for a couple of day. No blown fuses. I reconnected the switch. then the fuse blows again.
Replaced the switch. Never had a problem again.
See post 11 and 16
I assume the HST switch is not supposed to rotate and separate into two pieces? When I was removing the cannon plug the top would rotate 360 degrees and then easily slipped o
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traumadoc2b
Member
Equipment
B2650 LA534 BH77 bucket forks snow blade box blade flail grapple harrow rake
I have been dealing with the same OPC gremlins, repeatedly blown 5A fuse. Kubota dealer tried to tell me it was a bad fuel stop solenoid, but the tractor is shutting down normally, wouldn't be my first guess.
I have also had issues previously where the treadle pedal sticks just enough that the neutral safety switch prevents starting the tractor, so I was already familiar with this little bugger. I had not been able to pinpoint what I was doing each time the fuse blew, but after looking at the wiring harnesses for potential shorts, I decided to disconnect the HST pedal neutral safety switch and jumper across it with a short piece of 16 ga wire and 2 male spade connectors. Was able to operate the tractor, including PTO, for an hour without issue.
I called dealer and new switch is over $50. I thought to look on eBay and found them there listed for about $25, needless to say I'm ordering one online.
I have also had issues previously where the treadle pedal sticks just enough that the neutral safety switch prevents starting the tractor, so I was already familiar with this little bugger. I had not been able to pinpoint what I was doing each time the fuse blew, but after looking at the wiring harnesses for potential shorts, I decided to disconnect the HST pedal neutral safety switch and jumper across it with a short piece of 16 ga wire and 2 male spade connectors. Was able to operate the tractor, including PTO, for an hour without issue.
I called dealer and new switch is over $50. I thought to look on eBay and found them there listed for about $25, needless to say I'm ordering one online.