Fried ECU

SDT

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As I understand it, as the battery dies, the alternator output goes up. Apparently, there is no voltage or amperage (I'm not an electrician) limiter, hence the very high alternator output is what actually fried the ECU.
A so-called "load dump" was a significant issue in the early stages of automotive electronics.

In one of my former lives, I worked with a team studying this issue and how to protect the system electronics, most specifically the ECM from this phenomenon.

A load dump occurs when a battery connection is opened (regardless of how and for what reason) while a rapidly spinning alternator is charging the battery. When this occurs, a large amount, of energy (have forgotten specifics) can be immediately applied to the electrical system, raising the system voltage exponentially before the voltage regulation system can shut down the alternator, damaging just about anything that is connected at the time, e.g., light bulbs, radios, ECMs, etc.

Disconnecting the battery, intentionally or otherwise, while the alternator is charging causes this condition. The amount of energy "dumped" onto the electrical system will depend upon the amount of energy in the magnetic field of the alternator at the time of the open circuit, which, overly simplified, will depend upon the capacity and rotational speed of the alternator and the charge current at the time of open circuit. The energy can be several joules. The amplitude of the resulting voltage spike on the electrical system will, again overly simplified, depend upon the impedance of the various loads connected to the system at the time of disconnect.

With respect to automobiles (modern tractors are similar in this regard) this relatively infrequent phenomenon did not become a serious concern until the introduction of expensive electronic engine controls in 1980.

I have no idea what measures tractor manufacturers have taken to protect electronics from this phenomenon or even if such manufacturers are aware of the issue.

Those of you who who remember automobiles of the late 60s may remember the introduction of so-called "astro-ventilation" by GM in 1968. Astro-ventilation included, among other things, the elimination of vent windows and the inclusion of blower motors that could not be turned completely off but only reduced to low speed. Keeping the blower motor continuously connected to the electrical system is one of the things that GM did to lower the impedance of the electrical system, which helped to suppress the voltage spike resulting from a load dump. The vent windows were removed to reduce costs and marketing seized upon the opportunity to sell these changes as a new feature.

SDT
 
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SDT

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M's have 2 year/2000 hour warranty whichever comes first (usually 2 yr). OR, another year on powertrain, as I remember. Powertrain consists of internally lubricated parts and the warranty handbook outlines it pretty good. 5 years on emissions.

Your tractor was a 2017? It's 2021. If you purchased in 2017, your warranty is expired. Emissions might still have some warranty but here is the deal....read on.

Limited warranty is administered by dealer. It covers defects in manufacturing and workmanship for a certain period of time. That is one of the limitations (hence "limited warranty"). It is not lifetime warranty to my knowledge. With that said, emissions "might" help with the ecu. The problem with that is, kubota's warranty dept needs to know what the ROOT cause of the failure is. If they were able to deem that the root cause was a failed battery, a battery is coverd by the original warranty only (and actually may have it's own separate warranty?). Since the root cause has nothing to do with what powertrain and emissions limited warranty covers, you have a problem to deal with.

Notice I am not defending Kubota or anyone else here, it's just the way warranty works. Warranty is almost always called a "limited warranty" because, as said, has limitations. It is not insurance although if you had insurance they "might" take care of you (although they generally don't cover mechanical failures that are not accidental).

And finally all companies including Kubota are cracking down on warranty abuse. They are going by the books and anything "gray" is not covered. Unfortunate but it's only a sign of the times. People (and dealers) have been abusing warranty forever; and when I worked at the dealer I saw it OFTEN (daily several times a day usually), particular with lawn & garden equipment (Kommanders come to mind....). Just within the last year I saw changes in the warranty department that were not condusive to good customer service. I didn't and do not expect them to pay for everything, but there were times that they should have, but didn't--hence the phrase "gray area"--they were generally repairs that were not black and white defective. With that in mind, 88% of all of my warranty claims from 2019 through 2020 were not really warranty, they were obvious neglect, abuse, and accident, although we felt sorry for the consumer and took care of them. Kubota is smart and they know. Nowadays they want ECU data (codes), pictures, they're doing fluid analyses, they need to know this stuff to know if a failure it their fault or the fault of someone else, and the biggest reason for that is NOT so much to get out of paying for something, rather to point them in a direction that helps them build better equipment. Remember they have to compete with Deere, and now Cat, Komatsu, New Holland, and a bunch of others, so their product and service needs to be competitive. Unfortunately it also means that some repairs just aren't free anymore.

If your dealer doesn't want to give you any clear cut guidance or good explanation, move up the ladder-call customer service, and they'll get the field service rep involved.
Agreed. Warranty fraud has been rampant almost since the inception of warranties.

In yet another of my former lives, I was involved with warranty analysis at a major US auto maker.

At the time, manufacturers were well aware of warranty abuse and accepted a significant amount as a cost of doing business. Only egregious abusers were addressed.

Times have changed. Competition has increased greatly and margins have been reduced accordingly. Manufacturers can no longer afford rampant warranty abuse.

Interesting story concerning one example of systemic warranty fraud: In the late 60s, I worked summers in the parts department of a Chevrolet/Oldsmobile dealership. Customers would bring relatively new Oldsmobiles in for service and techs would bring repair order to parts counter to get oil filter, PCV valve, air filter, etc. I would give parts to tech and record part numbers of whatever was needed onto repair order. Tech would service car and place repair order back into slot on wall hanger.

Later, service manager would bring repair order back to parts counter instructing me to add rocker cover gaskets and valve seals. OK, I'll get them. No, I don't need parts, just add part numbers to repair order. Shortly, I noticed that this was happening for just about all late model Oldsmobile V8s so I started watching what was actually done to the vehicles. Of course, no valve seals were being changed. I also noticed that such was not being done to Chevrolets. Practice went on all summer, no doubt not just at our dealership.

Turns out, Oldsmobile had a campaign instructing dealers to replace valve seals on Oldsmobile V8s if customer complained of excessive oil consumption. Chevrolet had no such campaign. Service manager was charging GM for valve seal replacement on all Oldsmobiles that came in for service without doing the work. Could get away with such at the time as job was nearly all shop labor and there was no evidence, i.e., failed parts to hold or send back.

I have no idea how long (if ever) it took GM to get this abuse stopped, and this was back in the day of manufacturer service engineers who visited dealerships periodically. Later, in the 90s, GM eliminated service engineers to save costs, turning over such responsibility to dealer service managers. One can imagine how that worked out.

SDT
 
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GreensvilleJay

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The one big issue I have is the ECU 'fried'. While I only have 6 decades of design/build/sell electronics(3+ decades of 'microcontrollers', and 'ECU' should be designed to protect itself from 'abnormal'foreign' voltages and/or currents. This design isn't 'rocket science', just basic PROPER design and construction of the ECU. I see 'fried' boxes often,that WOULD still be working had a 50 cent part here or a 25 cent part there been installed. Classic is a line of 'electronic ignitions' for older tractors. NO protection from reverse polarity or over voltage.... sigh, $2 of parts from RatShack would prevent 'poof...oopsy..fried....'
Without seeing the schematics I don't see HOW a 'bad' battery can take out the ECU..unless the Alternator regulation is done IN the ECU, if so , then the problem IS bad design, straight from the factory. A weak or 'shorted cell' battery should neve rbe able to take out an ECU.
More common problem , is the krappy design/wiring of CANbus systems...THOSE 'engineers' need to work on THEIR junk in the field when it fails......
 

SDT

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The one big issue I have is the ECU 'fried'. While I only have 6 decades of design/build/sell electronics(3+ decades of 'microcontrollers', and 'ECU' should be designed to protect itself from 'abnormal'foreign' voltages and/or currents. This design isn't 'rocket science', just basic PROPER design and construction of the ECU. I see 'fried' boxes often,that WOULD still be working had a 50 cent part here or a 25 cent part there been installed. Classic is a line of 'electronic ignitions' for older tractors. NO protection from reverse polarity or over voltage.... sigh, $2 of parts from RatShack would prevent 'poof...oopsy..fried....'
Without seeing the schematics I don't see HOW a 'bad' battery can take out the ECU..unless the Alternator regulation is done IN the ECU, if so , then the problem IS bad design, straight from the factory. A weak or 'shorted cell' battery should neve rbe able to take out an ECU.
More common problem , is the krappy design/wiring of CANbus systems...THOSE 'engineers' need to work on THEIR junk in the field when it fails......
Generally agree but a load dump is an entirely different animal than an inductive kick from a relay coil or AC compressor clutch. MUCH more energy to contend with.

I have no idea what happened to the OPs ECU but the rare load dump cannot be ruled out.

Trying to suppress this amount of energy at the ECU is difficult, expensive, and not always possible.

SDT
 

GeoHorn

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If an alternator-equipped vehicle is operated without a battery in the circuit.... voltage spikes can exceed specifications and damage system electronics. In addition to a storage place of electrical energy the battery also acts as a giant capacitor (shock absorber).
Never operate an alternator-equipped engine with the electrical system energized unless a battery is properly installed.
 
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GreensvilleJay

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re: Trying to suppress this amount of energy at the ECU is difficult, expensive, and not always possible.
Not difficult or expensive IF you understand the 'nature of the beast', the real problem is 'they' don't want to pay a few dollars to prevent the 'million in one chance'.....but... if you make 5 million units, statistics says 5 WILL get zapped...,Say it costs a buck to prevent it, ,well 'they' saved 5 million dollars, and oh ,well.. 5 customers have to pay $2700 for a new ECU...
 

kubotafreak

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SDT, is completely correct. The battery not serving as a capacitor of sorts, will allow instantaneous voltage spikes. Buddy of mine fried his diesel truck ecu yesterday over cranking bad batteries. This is a rig that has two in parallel. Is it rare, yes, is it impossible, absolutely not. This is with factory configuration, and no additions outside of factory circuits.

Now on the other hand in my experience, 90% of my encounters of fired electronics involve some sort of other failure. Being someone shorted something(bridging the terminals), adding circuit loads outside of protection, or part failures. The factory cant replicate every type of end load failure. How many people actually pull the battery terminals when working on the rig, not many. Ill admit I've shorted a battery myself, luckily the battery saved my components from damage. Electronics wear out over time, board capacitors go bad, diodes burn out. Invisible static off your body alone can be on the order of 50k volts.

What will be the real kicker is when the second ecu goes because the original problem still exists…

Kubota's fault, prob not. It made it since 2017. How many people add lights, chargers, cameras, and don't have any issues...

Needless to say my buddy didn't make one comment about it being Fords fault for the ecu.

First thing I do when I get a new to me anything is look for all the **** the previous you-tube watcher installed.
 
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SDT

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re: Trying to suppress this amount of energy at the ECU is difficult, expensive, and not always possible.
Not difficult or expensive IF you understand the 'nature of the beast', the real problem is 'they' don't want to pay a few dollars to prevent the 'million in one chance'.....but... if you make 5 million units, statistics says 5 WILL get zapped...,Say it costs a buck to prevent it, ,well 'they' saved 5 million dollars, and oh ,well.. 5 customers have to pay $2700 for a new ECU...
Difficult, expensive and not always possible.

I understand load dump rather well.

Few folks have even heard of it.

SDT
 

GeoHorn

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Agreed. Warranty fraud has been rampant almost since the inception of warranties.
...valve seals on Oldsmobile V8s if customer complained of excessive oil consumption. Chevrolet had no such campaign. Service manager was charging GM for valve seal replacement on all Oldsmobiles that came in for service without doing the work. Could get away with such at the time as job was nearly all shop labor and there was no evidence, i.e., failed parts to hold or send back.

SDT
When I worked as a Toyota tech (mid-1970s) I had to turn in EVERYTHING ...including old gaskets ... Anything on the Work Order parts-list which was replaced went into a plastic bag except fluids. The bag remained in the parts dept until the Svc Mgr OK’d disposal. The primary reason was to support the warranty claim, but it also served to educate curious customers who wanted to know exactly what we did. The small parts (gaskets, seals, etc) were tossed after the customer had seen them. The larger parts (actual cores) were sent in to main distribution for dealer payment/exchange.
 

SDT

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When I worked as a Toyota tech (mid-1970s) I had to turn in EVERYTHING ...including old gaskets ... Anything on the Work Order parts-list which was replaced went into a plastic bag except fluids. The bag remained in the parts dept until the Svc Mgr OK’d disposal. The primary reason was to support the warranty claim, but it also served to educate curious customers who wanted to know exactly what we did. The small parts (gaskets, seals, etc) were tossed after the customer had seen them. The larger parts (actual cores) were sent in to main distribution for dealer payment/exchange.
Different companies do and have had different policies.

At the time, valve seals, gaskets, etc., were not kept for inspection, etc., by Oldsmobile or Chevrolet Indeed, few things were, e.g., carburetors, radios, etc. This, of course, is one of the reasons that Oldsmobile could submit thousands of fraudulent claims for this issue.

Times do and have changed. Who knows what today's policies are, but I can attest that things became worse rather than better, at least for some time.

SDT
 

lugbolt

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Different companies do and have had different policies.

At the time, valve seals, gaskets, etc., were not kept for inspection, etc., by Oldsmobile or Chevrolet Indeed, few things were, e.g., carburetors, radios, etc. This, of course, is one of the reasons that Oldsmobile could submit thousands of fraudulent claims for this issue.

Times do and have changed. Who knows what today's policies are, but I can attest that things became worse rather than better, at least for some time.

SDT

Kubota requires dealers to retain ALL warranty replaced parts for 120 days. 6 months. And this is AFTER the claim is processed/paid--which can take months on it's own....

The downside to that is.....in the case where I worked, 6 months of warranty parts adds up QUICKLY, and it becomes a pile (a big pile) in one month, with no good place to put them. One place I worked had a neat shelf that spanned an entire wall of the shop (about 70 foot length) specifically made and labeled for warranty parts, by date and manufacturer (since we had 4 brands). It worked well as long as it was maintained. Every so often we'd go through and trash the parts that were out of date (over 120 days in kubota's case). BUT--it never fails, the day after the garbage truck runs, Kubota sends you an email requesting either photos or return of the warranty part that is out of date. So we resorted to keep them typically for about a year. Cleaning around Christmas. You talk about a pile of parts! Keep in mind we (or "I", more specifically) were doing around 190-220 labor hours per month. We stayed busy with warranty and customer-pay work. Too busy. My body paid the price too. You can do some math on that. I was being paid around $20/hr plus a bonus. Dealer was bringing in around $20,000/mo off of my work, paying me $4000 (gross). As for me? Nary a day went by that I didn't HURT, everywhere from head to toe. 20,000-22,000 steps/day (pedometer-prescribed). Work consumed me, totally. Get home from work, rest for hours. Not much energy left to cook dinner so I generally would eat frozen or prepared. Not good diet which made it worse. Sleep a few hours do it the next day. 5 or 6 days a week (2 saturdays a month) with a few hours off, 2 wk vacation and could not take more than 5 days at a time (so people wouldn't take all 2 weeks at once). No air conditioning in the shop, 105-120 in the shop daily poor electricical service such that when you plug in a couple fans, it trips the breaker. Last 8 months (Feb-Oct 2020) with poor heaters, which wasn't a big issue except for Feb/Mar/part of April)--it might have reached 60 if it ran all day and the doors STAYED down (rare). The concrete work was at best, poor...nothing level, standing dirt, rough concrete surface, cracked everywhere and a pair of streams that ran UNDER the foundation (right under both of the 9000 lb 2 post lifts). Keep in mind I take lots of pride in my work and I don't do poor work, period. I want 100% customer expectations to be met. I couldn't do that with the facility we had. Level a mower deck? LOL! It wears on you. After 3 decades, I went in on one saturday and said I've had enough, put my notice in and 2 weeks later left and haven't looked back.

side note, I was talking to a guy I used to work with and we had a pretty good conversation about time, life, and work. One thing he mentioned was that all we have (as humans) is time. We sell our time to our employers. If all we have is time and time is our life, then we are selling our life to our employers. Interesting thought, at least I thought so.

They've (kubota) gotten better but not by much. Now they're requesting digital photos of the unit, the serial number, engine number, AND the failure in question, then the part that caused the failure (causal part). I have know of other dealers who've used hybrid phototography which is wrong. IOW, they'd take pics of the unit, serial number, then take pics of someone else's failed part on a different machine or out of the warranty parts pile. This was done when I worked with Deere, although I heard of it at one of "our" (dealer chain) kubota dealers. I always lived by doing right, and not teasing a rattlesnake.

I'm sure they have good reasoning for doing things that they do but as a former tech, some things that they wanted were asinine. Like returning of a mowing deck to the warranty dept for inspection--even after pictures were clearly sent and the claim paid. They'd get the deck back (and no they don't always pay shipping/freight) and deem that it was customer abuse/neglect and at that point they debit our account the amount of the claim. Keep in mind, it was 11 months after the claim was processed and paid. It happened too often. Once is too often. But on the flip side I have experienced times when a repair was a cut-and-dried case of neglect, thus not warrantable, and we (I) would submit it as a pre-authorization for warranty coverage, knowing full well that they wouldn't pay for it. Days/weeks go by, customer's paid and picked his stuff up, and then warranty department authorized the repair under warranty (or sometimes as a goodwill). So then the issue there is having to get in touch with the customer who is probably not happy (they won't answer the phone) and (2) getting the accounting department at the dealer to cut a check for a few times thousands of dollars. Of course the customer if you could get in touch with them was ecstatic and immediately showed up for a check regardless of whether the dealer had the funds available or not. BTDT. After payroll was done at the little place I worked for, wasn't much left.

People just think that warranty is cut-and-dried and as you can see from just a few examples, it's complicated--but necessary. I advise most folks that if you have an issue, if it's an easy fix like tightening a bolt, just take care of it on your own if possible. If its something that is more involved, get the dealer and the manufacturer involved keeping in mind that they don't cover abuse, neglect, lack of maintenance, bouncing off of trees, rollovers, and transportation to and from the dealership. If you are on your Kommander Z251 and run it up a cedar tree trying to trim it and break the belt, chances are VERY good that you're gonna have a hard time getting coverage under the limited warranty, in those cases, fix it yourself or pay the dealer.
 
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whitetiger

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It's very simple, a part that is 1 1/2 years past warranty fails and damages another part that happens to be expensive. The warranty is past.
You can ask for goodwill, but I doubt you will get it.
 

HenryD

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My thanks to everyone who took time to respond and help here. Yes, I will explore the warrantee and Kubota corporate customer service on this issue - good advice. I kept the bad ECU and all the error codes are still coming up, as all I did was replace the ECU but I have no way to clear the error codes.

The sequence of events that supposedly caused the problem was communicated to me by the Kubota dealer service technician, who also saw this issue within the last 3 months on another unit. I'm not smart enouhg to figure all this out. I'm also not smart enough to speculate.

Open to hearing more. I'll keep this group posted on my progress. Good news is that with a new high quality barttery and the new ECU, tractor works great again.
 

GeoHorn

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Lugbolt... I hear you.... and so do many other workers.... yet, some things never change...including those who condemn Unions...who are FOR workers and who do a good (if inefficient) job of representing them.
This will undoubtedly raise a ruckus with some hardheaded “right to work” crazies...but it’s true...Very simply... A Union is merely the Most Basic example of Real Democracy In Action! Where the majority decides the best recourse for the people instead of the “rulers”.
Standing-by with Nomex-Suit On for flames.
 

torch

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As I understand it, as the battery dies, the alternator output goes up. Apparently, there is no voltage or amperage (I'm not an electrician) limiter, hence the very high alternator output is what actually fried the ECU.
More likely the other way -- if the regulator (inside the alternator) or the voltage sense line (outside the alternator) fails causing the voltage to increase, the battery is damaged from overcharging. The increase in system voltage can also damage electronics.

If one or more cells in the battery fail, then the remaining cells will be individually overcharged, but the over-all battery voltage cannot exceed the regulator voltage and there is no harm to the electronics elsewhere.
 

SDT

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More likely the other way -- if the regulator (inside the alternator) or the voltage sense line (outside the alternator) fails causing the voltage to increase, the battery is damaged from overcharging. The increase in system voltage can also damage electronics.

If one or more cells in the battery fail, then the remaining cells will be individually overcharged, but the over-all battery voltage cannot exceed the regulator voltage and there is no harm to the electronics elsewhere.
Battery cells are in series. If one cell connection opens, the result is the same as a disconnect. No cells will be overcharged.

Yes, conditions do exist that can cause alternator output voltage to greatly exceed regulated voltage transiently.

SDT
 

SDT

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Lugbolt... I hear you.... and so do many other workers.... yet, some things never change...including those who condemn Unions...who are FOR workers and who do a good (if inefficient) job of representing them.
This will undoubtedly raise a ruckus with some hardheaded “right to work” crazies...but it’s true...Very simply... A Union is merely the Most Basic example of Real Democracy In Action! Where the majority decides the best recourse for the people instead of the “rulers”.
Standing-by with Nomex-Suit On for flames.
Though I disagree with your premise, which calls what follows into question, I choose to let this one pass so that you can avoid the Nomex suit.

SDT
 
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