Diagnosing a serious CAN bus communication fault on a John Deere 8420.

This tractor had me stumped for a while. Took some serious diagnosing and testing to figure out what was crashing the CAN bus on this tractor. Engine would sometimes cutout or die and sometimes the transmission would default to neutral. Limited controllers would show up on the corner post display and there were no codes to follow.
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[@verlinswarey507]

A lot of the reason why I watch these videos is from the sheer joy I get because I’m not the one having to deal with these hugely complex problems!!! Especially the diagnostics! I mean,holy,holy cow. 🐮🐄

[@douglassellers7528]

With all the electronics on these things you still have the purely mechanical side still there. Makes me glad I'm retired and just watch. Great video.

[@rdyardie]

I stand in awe of your ability to solve complex problems. Thank you for sharing.

[@raycollington4310]

Well done sorting that puzzle Zeth. That tractor was well looked after and the farm a real credit to its owner. Thank you both.

[@LukeLong-oi4uc]

I’m glad I no longer run my field truck commercially. The electronics are so advanced these days. It was almost like you were speaking a foreign language diagnosing the first tractor. Lol I grew up on tractors and started farming on my own in 1983 as a 14 year old. After high school I started wrenching and made a career in the heavy equipment industry. It’s amazing how advanced equipment has become in the past 35 years. I prefer the older technology. Great content

[@alanclark639]

Ooo! I could feel the heat being generated by all those keyboard safety officers while you were deseating the cab - brave of you to video the evidence! Yet another run down of the crazy amount of diagnostics and subsequent reprogramming you need to do as the result of quite a simple problem. I see some others have mentioned Eric O so I'll chip in Ivan at Pine Hollow Diagnostics - an amazing guy for breath of knowledge and "keep on it" attitude - he succeeds so many times to fault find and cure where even the main agents have utterly failed - often firing the dread parts cannon with gay abandon. Great work Zeth. Btw - stunned again at the price of J.D. spares!

[@Mick6k]

When getting a seat out of the cab i usually drive a forklift to the back and then slide the seat out of the back window directly onto the forks.

[@douglaskrenik4102]

Did a similar thing when replacing the cab fans in my 6420. Seat out the back window.

[@deeppushp497]

Dilpreet singh kang Virk Kheda panjab malout muktsar 🇮🇳🇮🇳🇮🇳🥳🥳🎈👌👌🌾🌾🌾🌽💪💪👏👏🎉

[@deeppushp497]

Dilpreet singh 🦌🦌🇮🇳🚜🚜🚜🎈👌👌🌾🌽💪👍🆗

[@timjorden8329]

That wiring blows my mind. But listening to you explain it makes sense. Those tractors are just too complex for the average guy to figure out

[@jdtractorman7445]

This is why customers need to understand the amount of time that is charged to them for repairs. Not every repair is cut and dry. Testing, replacing, reprogramming, relearning, all of that takes time if you want it fixed right.

[@charlesleeneihaus592]

You will be forever fixing those complicated tractors John deere will like you

[@heatherkohlwey8379]

You get your yoga, cardio, and weight training all in one. Thanks for the great video. Stay safe, and God bless.

[@bernardjackson7119]

The worst destruction is are fire in cab behind the seat. 7230R working in cotton picking bales up burnt 90% of the wiring harness plus the fuse box powder extinguisher got it out. Eventually got it back together. New harness and fuse box. What an absolute nightmare to sort out

[@AJVAN_]

This just shows me how good and reliable old beasts are

[@redbovine]

For those wondering. That harness is in the neighborhood of $7000 plus labor. On those heavy seats I turn them around backwards and set them in the back window seal upside down.

[@jeromestrong5614]

Thanks for the ride along. Enjoyed learning alot from the Master. Have a Awesome day.

[@ZKMasterTech]

Glad you enjoyed it

[@Thedevontree]

If my tractor broke down and I saw you jump out the truck I’d be like thank you Jesus.

[@larrycole4438]

Maybe Boeing needs you to fix the problems they have. ZK YOU ARE THE MAN !!!!!!!!!!!!!!

[@joetrojan2568]

pretty cool how the seat doubles as a weight, smart thinking from JD

[@ZKMasterTech]

I’m not a fan…my back hurts lol

[@tynewydd100]

Well done gents. Excellent video. Beats watching TV. Speechless.

[@jasonpark1052]

Had an 8200 that did something similar. CCD voltage’s go crazy, Coolant temp goes max, fuel gauge goes empty, corner post all dashes, transmission defaulted to neutral and once in a while it would turn into a crank no start. Ended up finding a couple of wires including the ACU ground broken under the insulation on the console side of the armrest harness.

[@jessemaier8681]

Looks like your poor farmer customer is barely getting by! Great video

[@kevinknight470]

I was a Level 1 Tech on Industrial Extruders, I feel Your Pain Brother. Thank God I am retired. Don't know what You weigh, but You are worth Your Weight in Gold, great Diagnostic Skills. Bless You Sir.😃

[@farming4g]

Sounds similar to a story from Warren from western truck repair with a truck wiring harness... would throw a fit when it would warm up. Run around thinking its an ecu, and finding out later that it was a tiny wire buried inside loom. It's a reason why it's called wiring mess; incredible how a little wire or two can completely brick a machine. Makes you feel any better dealing with wiring, had to replace "end terminals" on a new holland TG tractor... basically a plug that in sorts that "completes the tractor circuits" That was a bugger to figure out until came across someone who had an exact same issue and said to try to change those plugs

[@jazzerbyte]

Great explanation of the clutch calibration activity. Wiring issues always seem to be the one least likely to consider.

[@Gazman110]

Brilliant video. I really liked all of the technical info. I may not of understood it all but I certainly got the gist. Many thanks

[@kevingilbert9695]

Great job on fixing the nightmare of a problem. If Deere keeps making these tractors this complicated, you can literally name your price.

[@tallboy49]

Unfortunately all machinery manufacturers are the same. Just money pits.

[@antnotforwar]

This tractor is probably about 20 years old, just imagine how much more complicated they are now.

[@JohanLind]

Superb work. Hopefully we only pay our dues one time regarding specific issues... Likewise with life in general. Have a nice day!

[@user-og9hd2sj8z]

Thanks for another great video ZK and Joseph. It was interesting and very informative and entertaining for sure. Wow and wow. That tractor you worked on and all those wiring harness issues was something else. Wow again. You and Joseph had a lot of work time invested in that situation. Never would have guessed that seat was that heavy, oh my goodness!!!! Both you and Joseph are good sized and you were struggling with that seat. Most certainly a two person job. Let me insert something here to you ZK. Thanks to you for helping Joseph learn his lesson trade. You are a great teacher and showing him how to do things. My compliments to you ZK. I was amazed at all you had to do on this tractor wiring harness and all of the diagnostic tests you had to go through. I thought you both were going to need a sleeping bag-ha!!!!! I learned a lot watching you do all the diagnostic tests and how to do it and how to read the tests and the final readings. Most interesting!!!!! The gear case on that X9 combine was something else for you to get off. Was really frozen on there. Amazing!!!!!!!! Guess that is about it. Thanks for a really good learning lesson on this one. You are a highly qualified technician ZK. You went through that diagnostic session like a breeze. Wonderful work. Thanks for everything. The Iowa farm boy. Steve

[@starkeythemadclimber]

Weve taken seats out the back window onto a pallet before. They are stupid heavy!!

[@johnlangley6449]

Man your help is a heck of some man power

[@ronaldhowson1589]

This problem is a great proof of there is tomutch tec k inside tractors and other and heavy equipment. You need this unit just need start and run and do the job they are designed to do designed to do and cost the owners a fortune to own

[@richkloempken8473]

I was.surprised to see the tractor had a CAN bus much like automobiles, especially being almost 20 years old! Found Eric on the South Main Auto channel up in western NY. He is the master of troubleshooting network issues when other shops and dealers blast the car with unnecessary controllers that there is nothing wrong with. Being in the northern salt/rust belt, Jesse’s ore corroded/broken network wires. Always looking for open, short, and 120 ohm termination resistance on the network wires… He even is able to look at network communication signals on a digital oscilloscope to diagnose communication issues when network controllers won’t communicate properly. At least you don’t have to work on crusty/rusty issues on Ag equipment!😊

[@TheVespap200e]

Thanks Zeth for the video! Always enjoy seeing some carnage footage too! That chopper gear case disassembly was impressive! Nice job! 😄👍

[@jimclary7309]

Zeth great explanation as always, that's way you get paid the big bucks. You're a hellfa technician to figure out this situation you always come through. Keep the action and knowledge coming. Catchya at the next one. Stay safe!!

[@andrewluymes2977]

Very similar to a problem I had with a 8330T. Most controllers didn't show up, I had dashes, water temp hot, Found a rodent had eaten through the 2 yellow and green can bus wires going the ccu. No other wires were eaten-its like he knew exactly which ones would cause the most havoc.

[@rawhideadventures9515]

Stay awesome dude.

[@badzioch64]

You should’ve used your crane to hoist seat into cab. Great channel. You are a master tech for sure

[@kevinrice2721]

Love my 8120, probably my favorite tractor of my personal seat time 50 years. I did buy a new 6145 last winter, it's my loader/auger/snow/mowing/sprayer tractor. Getting used to it after couple hundred hours now but a lot I wish it had like my beloved 8x20 series.

[@rudolfbenner4802]

darn good helper.

[@genechronister7085]

Another amazing vid! Very interesting and informative! Keep the deere's running

[@psychedelicgem]

I love your vids. You are like a space x fitter. You rock. There are so many models and variables and i love listening to your explanations. Im a dirty design engineer and i love your advice on stuff.

[@ZKMasterTech]

Glad you like them!

[@psychedelicgem]

Im fist pumping when you say 'no more codes'

[@psychedelicgem]

​@ZKMasterTech bro you are 🔥 you are a master !!! We say 'seco' in spanish

[@psychedelicgem]

What i dont get is why peeps in your tractor field dont just use normal bearings and fix them axially with keepers. This bullshot of press fits is sooo old school

[@psychedelicgem]

What im saying is bearings normally sized are sliding fit. Just put a slightly bigger bearing in to last longer whatever. Press fits and interference fits are lazy and cap

[@drbill44]

Oh CAN bus issues, you can chase your tail for a long time on those. I chased an open circuit clockwise on a F150 starting at the data link connector and found it under the drivers seat. If I would have gone counter clockwise I would’ve found it in a few minutes. Working in vehicle development most times harnesses weren’t available so you had to find and repair the issues.

[@donalddehaven3229]

Love this channel. Great content. A true master tech

[@marilynallen644]

Yeah when you learn it the hard way you tend not to forget it 😊

[@bennyharper862]

Enjoy your videos. So called farm machinery companies are as bad as the car companies for electronic stuff guaranteed to eventually fail . All a farmer wants is to plant and harvest. Everything else is a prayer

[@mfc4591]

Hectic stuff. It really gave you a dear John letter!

[@encajeagricola]

Seems complicated right there mate !!!😂😂😂 all my luck to you !!!

[@nathansparrow1416]

I rest the seat on rear window ledge and tie it from falling out .

[@taffysgarage]

Love watching the video zeth I learnt so much from you're videos

[@kerrygleeson4409]

Always interesting Zeth thanks for sharing 🦘

[@Wileybird03]

Doing good work buddy👍👍

[@buckweaver5960]

Great video keep up the good work

[@oldadthomas]

Thanks for the video!

[@ronniedavis3273]

Another great one Zeth!

[@ZKMasterTech]

Thanks!

[@user-te8xp8ml2n]

I really enjoy your videos

[@steveanderson4768]

Wow, that tractor could’ve ended up opening up Pandora’s box a $2000 computer and a calibration versus an entire harness at $8000. I’m glad you’re not somebody just to throw parts at something. !!!

[@stevetrowbridge7101]

Great video be safe Texas farmer.

[@deanfrancis6474]

Great job

[@davidwatt1399]

Hey mate I work on mostly earth moving equipment in Australia and any time we get any sort of data link or can bus faults we go straight to any of the after market stuff that has been added and 9 out of ten times that where you will find the problem Cheers

[@timstanford3443]

It is cool that you show the whole thing. We all have these things happen. Sucks you didn’t catch it before you removed that damn seat

[@danielbarwise8406]

Have done a full loom in 10 and 30 series. Not fun, especially reprograming controllers the old way. Can Bus is always a nightmare ;-)

[@johnlangley6449]

Daunting is an understatement 😮 but ZK is on the job end of problem…problem.yeah 😅

[@mariohoncoop7612]

Maybe take out the back window and have acces for the crane on the truck to lift out the seat??

[@RichardThompson-gc1cf]

I HOPE THE RADIO PLAYS OK I LOVE MY 8 TRACK PLAYER

[@macdawg6403]

Nice Vid!

[@josephalaindaigle3194]

For the weight of that seat,I would consider a small boom like manufacturiers use😊

[@gcflower99]

Warren from Western Truck has entered the chat.

[@ianmckay1780]

The OL code is just about the most frustrating thing you can see. How do you know where to start, short to earth or just OC or something else. You end up removing umpteen different connectors some of which are not where you expect them to be. Then you find that that is ok, then go somewhere else and repeat etc etc etc... that is if you know what value you should have in the first place! Yes I know about such things, been an engineer on many types of different M/cs and done that even more. At least you didn't just pack up and go back the next day and try again, it gets to that stage sometimes,,,

[@jerryspangler6658]

Zeth , that seat can break youre back ! Smart to have help . Is there no room for any kind of lift system at all ?

[@DjNewcomeer]

Maybe it could be an idea to unhook the door cylinder and strap the door to the tail flasher to get some more space for this heavy seat Greetings from germany and Keep the green iron moving

[@donaldkrueger-lk6wp]

great.

[@agger838]

Expensive harmess

[@randydehne8866]

heck ya brother

[@tenthousanddays2103]

It sometimes takes a lot of green to keep that green iron movin.

[@johnwaby4321]

Nothing is easy to fix on tractors. Got to remove a lot of equipment just to get at the bit to work on . Well at least you did not have to replace all the harness 👍👍👍 So many set ups 😯. And then that A9 gave you sone trouble as well 😦

[@rednwhitecooper]

That’s nuts. Why won’t Deere let you just overlay a new twisted pair?

[@I_Died_2_Weeks_Ago]

Right! This would be the day I go independent. 😂 My goodness. 🤦‍♂️

[@ms-mac521]

👍👍👍

[@Ed_in_Md]

Joseph, I sure hope you understand all that electronic mumbo jumbo. The last tractor I drove was a John Deere B. Have you seen a model B? Ya, I’m old.

[@refurbansuburban]

Why didn't you stick your truck crane into the cab?

[@mitsnevets]

You slipped that seat right out of there

[@DougsHomestead]

Check each wire to ground...

[@ivoryjohnson4662]

Earned your money the hard way

[@JulianMoore-kx6op]

Hi Zeth. Great video. Yup that crane of yours could have taken some of the load of the job oyking that bloody seat in and out. Julian U.K X KTGIM

[@dukefarms9155]

Hey zk, what’s the best way to go about taking the hvac venting apart on these tractors in the cab?

[@Big.Ron1]

Is the owner able to do these calibrations and code clearing or is it a dealer only thing? Thank you and be safe.

[@musthaveclutch]

Did you put old controller back in just to verify it was not somthing in the harness that might have corrected itself by moving it around? You need to get a scope,great for seeing what the bus is doing.

[@russelltalma5806]

I'm thinking with the correct angle, use your crane for the seat.

[@charlesleeneihaus592]

Just think what that repair will cost or is it on warranty

[@craigadair128]

It’s a beautiful tractor but close to 20yo at this point. Whatever the bill is you pretty much just have to pay it and keep trucking.

[@fyrman9092]

The sucky part is getting the seat out was the easy part😮

[@BRPFan]

Great video, Thanks! Does Deere have a Tech Support You can call who has seen this problem before? Would have saved You a lot of time, money and frustration! I know with AGCO they have a Tech Support phone numbers You can call and it was very nice to have that available!

[@michaelpasold5083]

Yes they do, it's called DTAC (Dealer Technical Assistance Center) It goes directly to the factory that manufactured the particular product.

[@SuperSecretSquirell]

The seat in a D8 is about the same weight. The only way to get it out of the cab easily is to lay the back as far back as possible, but doing that eats up valuable real estate for you to stand in. I hate pulling the damn things.

[@tractorfixrable]

When removing a seat I extend my crane into the cab. Buckle up the seatbelt and lift and retract

[@davidlieurance8194]

OMG!!

[@user-ox5qz3tv4c]

Hi zeth Look at Dtac 215732 it's saved us hours of diagnostic time. Not sure if it would work on ccd. I haven't tried it on older 8020,s

[@danb4558]

Often wondered how many feet or miles of wiring in total is on these tractors.

[@jasonking8041]

i believe i would’ve took the back glass out to remove the seat

[@adambabson9716]

Is there no way to use the crane for the seat?

[@diersirrigation]

Anyone else think cheech and Chong? First gear, second gear!

[@JimWhitaker]

You lost me shortly after taking the seat out. Then it turned interesting.

[@orrinandkarenhoppe3974]

Whats the cost of parts and labor