Traction Kubota Electrical Problem

[Bladeharvest]

Hi,
I have a Kubota B5200 that I have worked to death over the years.
Last weekend I decided to fix a loose fuse under the dash. The fuse was difficult to get to so I stupidly thought it would be a good weekend project to remove the dash, repair the fuse case and clean up the years of layered dirt behind the dash including the idiot lights, switches, etc.
When I put it back together and test started it the charge idiot light would not turn off. I removed the dash and checked every connection in the wiring harness. The fuel gauge, flashers, headlights, glow plug, oil light all work fine except now the charge light does not go off. I even charged the new battery which showed a full charge. I also tried reversing the polarity of the dynamo as suggested on another site to no avail. I am wondering if the voltage regulator has gone bad or if I have missed something.
Any suggestions as how to test the regulator are greatly appreciated.
By the way, I did make a schematic of the wiring when I unplugged everything. It is pretty straight forward and the Dynamo has only two wires coming out of it. One tested hot to ground.
Thanks!

 

[hayden]

I think the first thing I'd check is whether you are actually getting a charge or not. That will tell you if it's truly a charge fault or just a warning light malfunction. The easiest way to check is to measure the battery voltage with the tractor turned off, then fire it up and see if the voltage climbs to 13+ volts. If it does, then you are charging and the warning light is mis-wired somehow. If not, then you really have a charging problem. Next I'd measure voltage right at the dynamo output. If that's over 13V then it's your regulator or wiring. If no voltage, then it's the dynamo.

Good luck

 

[SPT]

I had a similar problem with my B2910 but it started with charge light flickering on and off and then staying lit. Thought it was either dynamo or voltage regulator. Turned out to be a corroded wire. I figured it had to be the mice that got up under the dash keeping things a bit wet if you know what I mean. I know you said you checked the connections in the wiring but where my wire broke was right at the crimped terminal end inside the plastic connection block. I didn't see it at first. Was able to get a new terminal on and back in the block.
You may have already checked that but thought I would mention it.
Good Luck.

 

[JOHNINMA]

My first tractor is a B5200 and as was already said by a previous poster check that the tractor is actually charging the battery at the battery posts. I have used a dremel tool with a wire brush attachment to clean corrosion off of various fuse holder contacts and grounding points with good results. Good luck, hope its something simple.

 

[Bladeharvest]

Thanks for your suggestions. I did check the voltage at the battery when not running and again when running. I got no difference so I tore every thing back down and traced every connecter looking to see if it was loose or for cracked wires. Finally I took apart the dynamo. It was caked in years of dirt. I cleaned it up and lubricated with electrical grade oil and put everything back together. While I was doing this I placed a battery charger on the battery to be sure it was topped of. When I was done the tractor started right up and the charge light went off after a second or two. I have ran it several times with lights on and it seems to be working fine.
Next project is to rebuild the hydraulic valve on the 1630 front loader.
Thank you for your replies and suggestions!