I have a M5700 that keeps blowing the AC control fuse which is 5AMP. The blower and the panel suddenly stopped working (the AC light on the switch did not luminate). I replaced the fuse with another 5AMP fuse and it ran fine for a minute, then the fuse blew again. I replace the fuse again and the panel works, the blower works, but it's not cooling. Any suggestion on what to look for?
Kubota M5700 AC Control Blowing Fuses
- Thread starter mooreaud1
- Start date
I'd first look at coil on clutch for signs of burning/melting. If it looks ok I'd test for 12 volts at coil. If there's 12 volts but clutch doesn't engage the clutch is burned out. If there isn't 12 volts, start at compressor going back toward switch looking for relay. If there's 12 volts in but less or none out the relay is bad. To confirm relay is the problem jump from + battery post to clutch using a 10 amp fused wire to see if clutch operates. Come back and report what you did or didn't find.
I checked the circuit and the clutch seems to work fine with the test but no 12V coming in. Tomorrow, I’m removing the roof so I can get to the relay. Hopefully, I’ll find the problem there. Thanks for your help.
Ok, I removed the roof and found the relays. One is for the AC/Blower and the other is for the clutch. I tested the the relay with a test rig the coil activates and the continuity is shown on a meter when its engaged. If I jump the relay terminals the clutch works so it’s good to the relay but the relay is not seeing the signal to switch. I can only think it is the switch on the panel. Does this make sense?
These are from my B2650 WSM which is identical to the LX2610 WSM. Maybe Kubota uses the same thing on yours.
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Thanks, but it’s a M5700 and it is totally different. I have a shop manual. I wish I could find the switch diagram but I can’t find it in the shop manual. Thank you for the info. I wish it was useful in my situation.
Both of my manuals have it in the Cabin section under Servicing, chapter 6. Weird spot to place electrical content.
I found the issue. I was assuming it would be the relay, but it wasn’t. It was the actual switch on the control panel. I tested the switch and found it bad. Being very hesitant in thinking I found the real problem since it blew fuses at first, I checked for any potential short between the switch and relay and found none. The switch looked pretty cheap so I searched for a common switch that would save me money and couldn’t find one. I had to buy the switch from Kubota. It was $97 but it did come with the harness and connector. That seemed to fix the problem. AC works great now. Thanks for all the help from everyone.
Here I am in 2025 with the same issue. I haven’t taken the roof cover off as of yet, but the AC failed again in the same way. The AC worked fine since 9/23 but today it blew another fuse. Changed the fuse and the panel works but the AC switch doesn’t work. If it’s the switch again, any ideas on why this keeps happening. I looked for shorts last time but never found any. Now, I will say it was 95 degrees yesterday. Any idea on a heat related failure?
Since switch was the problem in 23,do same tests as you did in 23 but in reverse order this time.
As for paying $97 for a switch, I'd buy a universal 10-20 amp switch for $20 and fabricate mounting. Describe switch, how many positions does it have and what is each position for? How is it mounted?
As for paying $97 for a switch, I'd buy a universal 10-20 amp switch for $20 and fabricate mounting. Describe switch, how many positions does it have and what is each position for? How is it mounted?
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,
$97 is mighty pricey for a 10 amp switch ! Post a picture, has to be an economical part 'somewhere' ! Also post any markings like make, ID, etc. on the switch.
As to why it fails...I suspect the switch is rated for 5 amps as it's fused for 5 amps BUT inrush current is a lot higher. Also see IF the switch says AC 5 amps or DC 5 amps. materials used for DC switches( and relays) are different than AC units.
I would need to see the actual wiring diagram to see what's going on..
As to why it fails...I suspect the switch is rated for 5 amps as it's fused for 5 amps BUT inrush current is a lot higher. Also see IF the switch says AC 5 amps or DC 5 amps. materials used for DC switches( and relays) are different than AC units.
I would need to see the actual wiring diagram to see what's going on..
I agree, I just thought maybe the original switch was defective. What’s nuts is the original switch is a 5 AMP switch. All it does is tell the relay to switch. I found a 30amp that I’ll make work. The hole for the switch is square and I can’t find anything that fits that hole. I have checked for shorts and can’t find any. I’m going to replace the relay (its only $20) just in case its something intermittent with that. I come from the pro audio world and I have seen so many push button switch’s fail. Most manufacturers stopped using them. That being said, Kubota did a lousy job on the whole panel. You have to take the roof off to get to the panel. If you loosen the screws from inside the cab on the ac/heater control panel, the screws have nuts on the other side that will fall off. It is an absolute pig to get the panel back on by yourself.
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,
so... does the switch 'pop into' the square hole , with tabs to retain it there ? If so I used a lot of them decades ago, 7/8" square holes ( common in computers....). if just a SPDT ( 2 tabbed) switch, you could make square washer with hole to fit switch, then place one on switch, feed switch through panel, 2nd 'washer' on top, then nut.
As for the PITA BS to service the roof, yeesh.......
As for the PITA BS to service the roof, yeesh.......
The only thing that fuse supplies is the AC and blower relays. A total of maybe a half an amp total to power the coils in those relays. If the switch were bad it would have to be shorting to ground which is possible but you should be able to see and measure that at the pigtail off the switch. All of the wires for the rotary or blower control section are return or ground side of that circuit.
I would find it more likely you have a short in the harness somewhere and installing the new switch moved wires enough to eliminate the short until now.
I would find it more likely you have a short in the harness somewhere and installing the new switch moved wires enough to eliminate the short until now.
I was thinking the same thing. The harness is hard to trace. i‘ll see what I can come up with. Thanks to everybody that has replied.
Well, replaced the switch with a toggle that came with a plate from Amazon for $5.95. Works great. I have wiggle the harness and examined the runs. Fuse won’t blow. I’m totally miffed at what is causing this. It’s so intermittent…
Yes , that’s very possible. It’s a really cheap switch and the runs on the circuit board are tight. You could see where the burn marks were. Like I said, this is the second time with the same problem. Could be a Kubota screw up. Hopefully, it’s fixed now.