John Deere X300 Won't Start Now

OldToroGuy

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So it's the beginning of the mowing season for us and I put my X300 on the charger for awhile. It still didn't have much battery voltage so I jumped it with a regular 12 volt car battery in my Cub Cadet compact tractor. The JD initially started right up and then quit, now nothing! I checked the fuses on the firewall and the 15 amp fuse was blown. I replaced the fuse but still no start, no clicking, nothing. My Owners Manual says it could be a fusible link. Where is the fusible link on an X300 and what does it look like? Would my slightly larger 12 volt tractor have blown a fuse? Yes it was hooked up correctly. I went to a John Deere parts site but couldn't find any reference to a fusible link and my manual says to check with the dealer. Surely I don't need the dealer to replace the fusible link?
 

StarTech

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The X300 wiring diagrams show two fuse links. One from the B+ of the voltage regulator to the Battery side of the starter solenoid. The second one comes off the battery side of the starter solenoid and heads toward the fuse block via an interconnect. Basically the fuse link just any like regular electrical wire in appearnce. In this case they are Red.

JD will not just sell the fuse link but want you buy the MIU11332 harness. IF you are able to find fuse link and it is blown simple cut it out and a fuse holder and fuse of 30-35 amps as the lights are fused at 15 amp and starter relay at 20 amp and both circuits are active during cranking. Now the service does not give the reduced size wire use for the fuse link. The wire is under sized so it burns in two at the correct amperage.

Th only image I can find of the harness is one on the IPL. It is item 23.

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Auto Doc's

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So it's the beginning of the mowing season for us and I put my X300 on the charger for awhile. It still didn't have much battery voltage so I jumped it with a regular 12 volt car battery in my Cub Cadet compact tractor. The JD initially started right up and then quit, now nothing! I checked the fuses on the firewall and the 15 amp fuse was blown. I replaced the fuse but still no start, no clicking, nothing. My Owners Manual says it could be a fusible link. Where is the fusible link on an X300 and what does it look like? Would my slightly larger 12 volt tractor have blown a fuse? Yes it was hooked up correctly. I went to a John Deere parts site but couldn't find any reference to a fusible link and my manual says to check with the dealer. Surely I don't need the dealer to replace the fusible link?
To answer the question about the larger battery... yes it will blow fuses and fusible links because the Amperage is too much for the circuits on the rider. Voltage is just the basic power potential; the real power comes from the Amperage a battery has stored. The compact tractor was likely a 600 Ah battery while the rider was around a 300 Ah battery.

When you check the fuse link wires, tug on them to see if the insulation stretches, that will indicate it is broken, they do not always burn through the insulation because it is heat resistant.

Fusible link wire can be purchased at most parts stores, but you have to know what gauge. Typically, if your main power wires that have fusible links in them at the starter are 10-12 ga. then a 14-16 ga fusible link would be sufficient. The larger starter cable does not have a fusible link. (Note: The higher the gauge of the wire the small diameter of the total strands it will have.)

A fusible link is a safety device like a fuse, but it can temporarily handle high Amp loads for a brief period whereas a fuse would immediately pop the center element open.

Whatever you decide to install, it needs to be soldered and shrink taped at the connections. Quick butt connectors will create problems in a short time due to moisture and dirt exposure.
 

OldToroGuy

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Thanks for the tips on this, depending on the weather I may get back to it tomorrow. I tried to look up a wiring diagram but I couldn't find what I wanted on the JD sites. On other items, (Honda motorcycles for example), I can find most things right down to a washer, I couldn't break the code on this one though!
 

StarTech

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To answer the question about the larger battery... yes it will blow fuses and fusible links because the Amperage is too much for the circuits on the rider. Voltage is just the basic power potential; the real power comes from the Amperage a battery has stored. The compact tractor was likely a 600 Ah battery while the rider was around a 300 Ah battery.

When you check the fuse link wires, tug on them to see if the insulation stretches, that will indicate it is broken, they do not always burn through the insulation because it is heat resistant.

Fusible link wire can be purchased at most parts stores, but you have to know what gauge. Typically, if your main power wires that have fusible links in them at the starter are 10-12 ga. then a 14-16 ga fusible link would be sufficient. The larger starter cable does not have a fusible link. (Note: The higher the gauge of the wire the small diameter of the total strands it will have.)

A fusible link is a safety device like a fuse, but it can temporarily handle high Amp loads for a brief period whereas a fuse would immediately pop the center element open.

Whatever you decide to install, it needs to be soldered and shrink taped at the connections. Quick butt connectors will create problems in a short time due to moisture and dirt exposure.
Basic electronics/electric here. It doesn't matter how larger a battery is if the voltage is the same. Current is limited to the voltage divide by the resistance. Basically resistance limits the current draw. Now if you put in say a 24v in place of a 12v battery then yes the current would increase thru the same resistance.

If what you said was true then that 1000 CCA battery I installed in my truck would blowing all my fuses as it replace 550 CCA. (A = V/R (I = E/R))
 

Auto Doc's

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Hi Startech,

Probably, I should have added do not connect while the jumper vehicle (compact tractor or vehicle) is running.

I have dealt with way too many blown circuit fuses caused by customers jump starting off of a running vehicle or farm tractor.
 

OldToroGuy

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Well guys in-spite of my ability (or inability:() to jump start an X300 and all the info you gave me........it starts! I called a local JD dealer that has been in business for many years and told them my problems and the troubleshooting in the Operators Manual said the next thing to check was the Fuse-able Link. The guy spent quite awhile on the phone but couldn't find any fuse able link listed for my X300. I had checked the tractor earlier and I didn't find any wires that appeared to stretch when I tugged on them, etc. The battery that I had been charging for a day or so was high 9s to 10 volt, I also found the sticker and it was just shy of 8 years old.

I remembered 100 years ago when I went to an Automotive Tech School, the lead electrical instructor always said to "start with the battery" when you are diagnosing. If the battery is low voltage or toast it's a no go. So with the low voltage and age I bought a new battery. Guess what guys, the sucker started right up! So the 15 amp fuse I blew and the new battery corrected my not start problem. I had never tried to jump the battery on the X300 or on one of my motorcycles but I obviously learned a good lesson about not using a large battery for that. BTW I never started the compact tractor up I just attached the cables to the battery posts without it running. So thanks again for all everyone's help.

Here's another thing that you'll probably think I'm crazy. The full sized battery in my Cub Cadet 7234, 23HP Mitsubishi engine and drive train, I bought at Advance Auto and the sticker on it is for 2011. It is their Silver model but I don't think they sell that one now. I know it's old but the tractor is garaged indoors in the winter because I plow with it and it's always undercover even in the summers. I've been watching it know it will quit any time but it still seems to start the tractor.
 

Auto Doc's

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Glad to hear it is up and running now. Better save your pennies because the Cub Cadet will be next in line.
 
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