LX279 Ignition Module Resistor Burning Out

[THEDIESEL78]

Hey Everyone,

I have a John Deere LX279 lawI notice n tractor. I went to start it up this week and it the battery needed to be charged so I charged it up and it took right off and ran just fine. As I let it warm up, I noticed a burning electrical smell and a little waft of smoke coming out from under the dash. Looking things over, on the ignition module I noticed that one of the resistors had a blackend look so I talked the local John Deere technician and he said that I would need to replace the whole module. I swallowed hard and grabbed the $150 part and installed it like they said I would need to. I started the mower up and things were going fine until a couple minutes of running resulted in the same waft of smoke and smell from under the hood and the same burned up resistor. Does anyone have any direction on this for me? I would prefer not to fry anything else I have attached the picture of the first module. Thanks for the help!

 

[bertsmobile1]

I hope you have the old board because that is a common resistor so is very much replacable for under $ 1.00 .
However I will now ask you to spend even more money on the JD technical manual for your mower.
About $ 45 as a download from JD and would have saved you more than that this time alone.
I might suggest you double check the battery to ensure you have not put it in backwards .
My LX manual is only for the 172 to 188 and I only buy them on an as needed basis

 

[THEDIESEL78]

Thanks for your feedback. My battery is in the correct way. My questions is more so what is causing that resistor and capacitor to burn out? I am looking for a schematic that will show what those are connected to so that I might track down the problem and then most likely just replace those. Thanks again for the help everyone!

 

[bertsmobile1]

The wiring diagrams are in the technical manual .
There are generally a dozen or more depending upon the year of manufacture & which market it was made for.
This is why you need to buy the manual .
If I had one that covered your mower I would gladly copy the electrical section & send it to you but I don't
Unlike other companies where manuals are written by the CEO's idiot moron son and wiring diagrams are drawn by an equally ignorant fool , the JD manual is written by professionals so that total novices can read, understand & repair .
I have seen text books that are not as comprehensive, easy to read & understand as the JD manuals are .
My only dissapointment is I did not need to buy one earlier in my new life as a small engine tech, it would have made the learning curve a lot smoother.
The only board I have fixed was on one of the rebadged Yanmar diesels it was blowing because of a wire that was broken at the terminal block where the crimp was so it was just touching till the mower started to move when it would make & break which did a similar thing to your board . Original replacement board was over $ 300 ( Aus) and the second one was of course a warranty job ( ouch ) but I kept both of them, repaired both & sold both for $ 250 a piece so ended up OK .
I would never have found the bad joint without the manual and the comprehensive testing proceedures detailed in the book where you are shown what to test, where to put the probes and where the controls need to be set before you start testing . There are no "magic boxes" like you see in other manuals where a bunch of wires are shown going int a secret "MIR Module " everything board is shown in detail .
I can not recommend the JD technical manual high enough .

 

[THEDIESEL78]

Does anyone have a pdf copy of the Technical Manual?