JD5425 no electric power

[nckennedy]

Tried to start it the other day about 25 degrees outside, but after turning switch on there was no dash lights, no radio, would not turn over, etc. However the 4 way flashers still work and the work lights are working. Battery is good, but the 20 amp (ignition fuse) F1 was blown. So I put another one in and it blew immediately. So I disconnected the power to the cold start thermostat. But that didn't help. All the other fuses seem to be fine. So I am thinking it might be starter or ignition switch. Any thoughts or ideas what might be causing this situation?
Thanks,
Craig

 

[jaxs]

Any thoughts or ideas what might be causing this situation?
Thanks,
Craig

I can think of multiple possabilities but rather than guess and throw parts at it,I'd rather help you find which and fix it the first time with minimum frusteration and expense. There's different ways of skinning the cat depending on tools,knowledge and experience you have. It's also good to know if you just want to fix this and get back to work or if you want to learn electrical tronleshooting in general. Do you own a multimeter? Do you know what readings on various settings mean? If not a multimeter,a test light with alagator clips on pigtails? Soldoring iron?

 

[Roadworthy]

You put in another fuse and it blew immediately? Did you turn anything on or did it just blow as soon as it was installed? You'll need to isolate what is supplied by the fuse to narrow it down. A schematic would be a big help.

 

[nckennedy]

HI Yes, I do have a volt meter and have used it some for 100v 220v 12v continuity, etc. Yes the new fuse blew when I turned the key switch to on. Battery is good 12.8 volts, power to the fuse box, power to the alternator, power on the solenoid terminal (touched screw to frame- nice spark). I was going to see if I could find the ignition switch next and check it, but might be a big job to get into the dashboard.

 

[jaxs]

Nice tractor you have,I hope it gives you service equal to we had from 4020s. i loved those old Deeres so that I kept one which wound up a barn princess for lack of jobs fitting it.
Let's see if we can locate this short circuit. If your meter has overcurrent protection when set to amps,put it in series. This can be done accross blown fuse terminals,main fuse block supply wire or remove either battery cable and put amp meter between cable and post. If amps trigger overcurent protection or if your meter doesn't have that feature,simple put test light in series for now and we can make provissions for amp meter later if needed. Light will glow or meter will register amps. It's simple a process of disconnecting devices one at a time untll amp meter drops to less than 1 amp or light dim's. Since you suspect key switch,try and locate wire supplying power to switch and disconnect it. If fuse was blowing with key in off position,I seriously doubt the problem is in switch. If fuse was blowing only when switch on,turn key on while running above tests. If light flickers or meter reading fluctayes as wires and connectors are moved,look for insulation missing from a wire/connector. If problem isn't appearant by now and test light is being used,we need to regroup and work meter in. I should have asked about overcurrent protection before we started but you can let me know about that as well as max amp reading capacity of meter. Break time,update and/or ask questions as you please.

 

[Roadworthy]

If the fuse held when installed but blew when you turned the key the wiring to the switch is probably good and I suspect the switch is good as well unless one of the contacts is internally grounded. It would, as jaxs suggested, be helpful to start isolating circuits. One of them is apparently shorted to ground. It could be something as simple as the line to your oil pressure sensor coming loose or having the insulation chafed through at some point grounding it. Get a schematic if at all possible and start eliminating things one at a time. It would be counter productive (and costly) to replace the ignition switch and find your problem is exactly the same.

 

[nckennedy]

Yes, the tractor has been a blessing to us. I have the Kleen MM300 multimeter, but I am not sure about the overcurrent protection. Is there an easy way to know if I have it or not?

 

[workinonit]

It will have a fuse in the battery compartment. It has OC protection via a 10 amp fuse probably. If you are blowing a 20 amp fuse then you are going to blow your 10 amp fuse in your meter if you place the meter in series across the blown fuse terminals. Before you start shotgunning I recommend getting the schematics for the tractor and see what's on that circuit. I had a 5310 and mine did that a couple of times. I found it to be the fuel shutoff solenoid circuit that was causing the issue. Not thew solenoid itself but a thermister that was on the circuit. That lead is probably still lifted wherever the tractor is today.

 

[jaxs]

Your Klien mm300 is more than adiquate for diyer but is only capiable of 10 amps max,above which it will blow it's fuse as workinonit suggested. I wouldn't reccomend investing in a pro meter since the one you have will do 99% of what you are likly to incounter with residential and 12v dc systems. A test light is slower and less precise but should do what we need. I'm not familiar with this piticular tractor and would love that someone who is chime in with whether it normally has a small Ma drain like all cars since about y2k do. The significance is an led or other ma bulb will continue glowing even after short is eliminated. If you don't find it pretty quick and we are still in the dark about keep live current for computer,here's a poor man's method to overcome false indication due to computer draw. Fabercate a new test light/load using an old fashion headlamp,spotlight or other 2 to 5 amp device. Hook them to 12 volts and use your meter to check amps for things you have laying around. To make this Rube Goldberg a thing of beauty,connect a seatbelt,door or other buzzer/bell/alarm in parallel so that you not only have visual via light,you have audio that alow's turning your back while tracing circuits. The divice can be up to 10 amps but will discharge tractor battery faster. That isn't an issue if you have a charger but I wouldn't have charger on battery during testing. To recap what and how is going on. Presently short is pulling in excess of 20 amps,could be 50,100 or who knows. Our new Rube Goldberg limit's draw to what it consume's. More accuratly,if short is actually fixed amps rather than dead short,power can devide between Rude and load but we don't want to go far down that road since it tend's to foster conversation above and byound our need and pay grade. Anyho,connect Rude accross fuse terminals and note brightness. When and if short is disconnected,light will dim or go out. If Rude's draw is kept below 5 amps,we can connect him in series with mm300. With this arrangement, note reading on mm300 and watch for it to drop when short is disconnected (or in the unlikly event short is partly reduced. Don't overlook to unplug alternator as a possible source. No more (touched screw to frame- nice spark) while mm300 is in circuit,that can blow it's fuse. Feel free to ask questions and for clearification. I'm not even sure I understand all I know about this!
Y'll jump in here to offer tips and see that I don't cause op to set fire to his tractor.

 

[nckennedy]

A friend from church came over and tested the starter after we took off the tractor. Seems to be fine, but it does bring up another question. For about the last 6 months or so when trying turning the key, I get a grinding noise, as if the solend was missing its meshing with starter motor. Usually after one or two additional try it starts right up. Is it possible that the starter/solend is going bad? Its off the tractor now and would be a good time to change it out if that is true. Any thoughts? I will down load a wiring diagram later today and should be able to get back at trouble shooting tomorrow. Its been to cold and snowy the last few days to mess with it, but we are expecting a warm up tomorrow.
Craig