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Joined 2 years ago
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Cake day: July 23rd, 2023

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  • I appreciate your insights but struggle to reconcile the following with what others say (youtubers and folks in an electronics chat room):

    I doubt many people use eeprom to save any kind of error. … It is far more likely that the script is just a state machine and is reaching an error state because of some missing or bad signal that it needs to continue running the script.

    I asked EE folks how would a controller board sense a fault? Does the controller take resistance measurements on the components? The answer was “highly unlikely - that would be far more sophisticated and costly than what would be realistic in a domestic washing machine”. They said fault detection is based on logic. E.g. if the tacho sensor does not have increasing feedback despite increasing power to the motor, then the controller can detect from that that there is a fault. Or if the water has been filling for a long time and the pressure sensor is not detecting a pressure increase, the machine would know from that activity that the inlet valve has a problem.

    You seem to suggest that the script reruns from a clean state every time and that a “bad signal” would be re-detected each run, which then implies that the machine would repeatedly attempt to fill with water, tumble, drain, etc. But that does not seem to be what I am seeing. The machine will be powered off & unplugged for days, and when powered on it instantly flashes that there is a fault (which is likely only known after attempting to run the various components). This is consistent with what a Youtuber said: the machine (not my particular model but speaking generally) stores the fault code. From there, the machine is trapped in that state until the error code is cleared by pressing a secret sequence of buttons.

    Some leaked tech docs for a different model (same make) mentioned that if a fault occurs 8 times, it then becomes stored in memory. This seems consistent with what I observed. I repeatedly attempted to run the machine. Not sure how many times. Motors would run, failure hits, and then it quits. After doing that so many times (which I regret), the behavior changed. Now the machine will not even attempt to run because it is apparently trapped in an error state.

    So everything seems to point to the error code being stored in EEPROM (which I believe is embedded in the ATmega32L chip). And not just the error code but apparently a count of failed attempts to run a program.


  • I don’t intend to modify the program. I am just looking to reset the state of the software to get it out of the fault state.

    Normally that can be done by using the buttons on the PCB to enter a secret combination code to:

    • enter diagnostic mode
    • run various functions/cycles which normally run as part of a program
    • see the error code
    • reset the board

    When the software detects a fault (such as a broken pump), it saves the error code. Then if you fix the pump, the software doesn’t know the pump has been fixed. So the board has to be reset to clear the error code.

    The button sequence codes are secret and known only to the manufacturer. They are very protectionist. In Europe, law requires them to make the codes available to other 3rd party technicians – but only in the 1st ten years and they can also charge a fee. Consumers get no access under any circumstances.

    My thought was theoretically a pro independent repair service would not want to pay every manufacturer for the secret info for every model they repair – so perhaps they would attach to the USART serial port and have a way to see errors and reset the board. But if it’s as you say, then the USART is disabled and useless to repairers. Which means I’m stuffed because I cannot buy a replacement card for my machine.

    If the serial port is not disabled, you conjecture that it is likely a read-only non-interactive mechanism. That still may be useful. I was able to find the secret button combination that is likely giving me an error code which I can guess the meaning of based on leaked docs for other models, but I’m not satisfied with that. I would be useful if I could get more verbose or supplemental info about the error state.

    There is some chatter about GE washing machines (not what I have) include an rj-45 port and that they released some kind of open source thing called the green bean which adapts USB to serial. On the one hand, it suggests that not all manufacturers intend to prevent communication with the PCB. OTOH, this actually seems to not be for service use but for sending notifications to the user.








  • Thanks for the feedback! So I guess I should buy a megger. Wow… not cheap. I think I see these at local 2nd hand street markets. I often thought “what strange multimeter… so few functions” but I didn’t realize what I was looking at. I will look for something that dials “500V” and has fewer modes than a multimeter, and ideally a “MΩ” printed somewhere although it looks like they won’t all print that on the device. I should probably learn how to test the megger itself so I buy something that works.

    I suppose I could try to bring the motor into an appliance repair shop and pay them to test it with a megger.

    As far as diagnosis of the whole machine-- suppose it’s true that I have an insulation failure. The control panel LEDs light up correctly when powered on, then when I try to start a program the start button just blinks. Does it seem viable or likely that faulty insulation would cause the controller to behave that way? I get the impression that the blinking LED means the controller detected an unspecified fault of some kind & refused to continue, which tempts me to think that the controller is functioning correctly – unless it’s a false positive of a failure.

    I really want to avoid replacing multiple major parts because I don’t imagine I can return special ordered parts.

    (update) At the street market I saw something like this for €100:

    https://www.tekcoplus.com/cdn/shop/products/gain-express-gainexpress-Multimeter-SM-852B-set_1024x1024.jpg?v=1553658696

    which was apparently a lousy price. I also saw a megger for €160 that looked kind of like this:

    https://cdn.globalso.com/hvhipot/GD3128-Series-Insulation-Resistance-Tester2.jpg

    I guess that’s what I need. It’s probably a good price for what it is, but not justified for my mission.


  • Right but I think that safety capacitor (SC) is the last thing I care about. IIUC, I could perhaps even simply bypass the SC because it’s merely improving the power quality/safety. It’s not worth buying an SC unless I can fix whatever is broken. If I could get the machine working, I could then of course consider replacing the SC as a final protective measure – but I’m not even sure anything is wrong with the SC.

    The task at hand is testing every essential component of the washing machine, starting with the motor and tacho. I would like to understand what happened with the SC and motor though. Did I wire the motor wrong which caused the SC to flash and produce bad output for a moment? I don’t want to repeat that. I could power the motor directly without the SC, but if the motor is doing upstream damage then I guess I wouldn’t want my breaker box on the chopping block.











  • It basically is saying that if you have more money then you have more “votes”.

    That’s simply true. It doesn’t do anyone any good to disregard the facts.

    Or to put it in another way: If you have more money you matter more.

    That abstraction doesn’t help much. And first of all, it’s more accurate to derive the statement “If you have more money then you have more influence”.

    It’s still a shitty status quo, but it is what it is. The worse thing you can do is tell people not to boycott shit products on the basis of rejecting reality. It’d be like telling people not to vote in elections because their vote is a drop in the ocean.

    Some people vote for democrats, then they cancel their own vote by getting their internet service from Spectrum, buying fuel from Chevron for their car, shipping their packages using FedEx, getting their phone service from AT&T, banking at PNC Bank, flying on Boeing planes, shopping on Amazon, doing their web searches on a Microsoft syndicate’s site (e.g. DDG), buying Sony devices… etc. They either have no clue that most of their voting is actually for the republicans, or they think that drop-in-the-ocean vote that comes once in 4 years somehow carries more weight than the daily votes they cast with reckless disregard.

    Greg Abbott’s war chest is mostly fed by oil companies. If you buy fuel for a car, you help Greg Abbott and other republicans. And if you buy from Chevron, you give the greatest support to republicans (Chevron is an ALEC member).




  • Ending capitalism is not the /only/ way. Within a capitalistic system, you can boycott shit. Most consumers are pushovers but it doesn’t have to be that way. I’m boycotting hundreds of shitty companies. Off the top of my head:

    • Amazon
    • Cloudflare
    • Microsoft
    • Facebook
    • Google
    • Apple
    • (surveillance advertisers in general)
    • (all closed-source s/w)
    • HP
    • Proctor & Gamble
    • Unilever
    • all ALEC members (American Express, Anheuser Busch, Boeing, CenturyLink, Charter Communications, Chevron, FedEx, Motorola, PNC bank, Sony, TimeWarner)
    • many shitty banks
    • Paypal
    • AT&T
    • GMA members (Coke, Pepsi, Kraft - Heinz, Kellogg’s, General Mills, McCormick, Hormel, Smucker)
    • BetterThanCashAlliance.org members (visa, mastercard, unilever) – war on cash
    • Bayar-Monsanto
    • Dupont
    • Hershey
    • Nestlé
    • Exxon/Mobil
    • Comcast
    • Koch
    • Home Depot
    • Lowes
    • …etc

    Those are all shitty companies that significantly worsen the world. Giving money or data to any of them contributes to enshitification of the world.

    Of course it’s an option to stop supporting assholes. Become ethical. Be the change you want to see.






  • emphasis mine:

    Anti-nuclear is like anti-GMO and anti-vax: pure ignorance, and fear of that which they don’t understand.

    First of all anti- #GMO stances are often derived from anti-Bayer-Monsanto stances. There is no transparency about whether Monsanto is in the supply chain of any given thing you buy, so boycotting GMO is as accurate as ethical consumers can get to boycotting Monsanto. It would either require pure ignorance or distaste for humanity to support that company with its pernicious history and intent to eventually take control over the world’s food supply.

    Then there’s the anti-GMO-tech camp (which is what you had in mind). You have people who are anti-all-GMO and those who are anti-risky-GMO. It’s pure technological ignorance to regard all GMO equally safe or equally unsafe. GMO is an umbrella of many techniques. Some of those techniques are as low risk as cross-breeding in ways that can happens in nature. Other invasive techniques are extremely risky & experimental. You’re wiser if you separate the different GMO techniques and accept the low risk ones while condemning the foolishly risky approaches at the hands of a profit-driven corporation taking every shortcut they can get away with.

    So in short:

    • Boycott all U.S.-sourced GMO if you’re an ethical consumer. (note the EU produces GMO without Monsanto)
    • Boycott just high-risk GMO techniques if you’re unethical but at least wise about the risks. (note this is somewhat impractical because you don’t have the transparency of knowing what technique was used)
    • Boycott no GMO at all if you’re ignorant about risks & simultaneously unethical.




  • What’s the reasoning behind that ban?

    The drain infrastructure in most US cities is relatively modern. The city drain pipes are big & thus able to handle a big amount of food waste coming from residents. I think I heard some minority of US cities also ban garbage disposals because for whatever reason their pipework can’t handle the load.

    Old cities have small pipes that could not sustain the onslaught of thick food waste, as I understand it. In my city, rats outnumber humans by 2 to 1 and I think they thrive in the sewer. So I’m not sure if it’s also an effort to not feed rats. In any case, the city’s preferred way of dealing with waste food is to put it in the trash.

    Recently they required food waste to be separated into a different color bag than the others. So they collect the food waste together and compost it. In the end, this is probably the most forward-thinking approach despite the sewer system being quite behind.


  • I can’t quite work out if you’re making a prediction of a clog returning, or if you’ve not realized that there is no longer a clog.

    For weeks I have been fighting clog. But the clog is finally gone and the drain is now faster than I have ever seen. The drain actually keeps pace with the faucet on full blast. In the past, even in the best of times, I think the fastest it drained was 1 liter in 20 seconds. Now 1 liter drains in 6 seconds.

    You’re already hundreds of dollars into gadgets and chemicals. Stop it. Cut your losses and call a professional next time.

    Pros give different results in different areas. I called a plumber for a leak once. I was out of town, but a simple leak was dripping and forming a puddle on the floor. The leak was in exposed PEX pipe visibly strapped to the wall (yes that room is quite ugly). The plumber spent little time, failed to find the leak, blamed something that was fine, and charged €200. We called him back and he made the outrageous claim that the puddle was due to “condensation”. Left and gave no refund. I would love to have a reliable & trustworthy plumber. But since I don’t have that I have to become the plumber.

    My costs in the drain fight were ~¾ of €200 (less than the incompetent plumber’s charge for simply showing up). Every time I redo the pipes I’m appalled by the work of past plumbers. So I think I’m just not in a good place to hire plumbers. There is no quality control of any kind in my area. No Better Business Bureau of sorts to record complaints. So the infrastructure is not setup for bad plumbers to fail.


  • Ok, so as you noted at the end, sulfuric acid was a bad idea for the pipes.

    Not exactly. The sulfuric acid likely solved my problem (in combination with a plunger). It overflowed a little & attacked radiator pipes due to me underestimating the foam expansion rate (user error - perhaps poured too fast), but AFAIK it did not harm the drain pipes. Sulfuric acid would not be a good early stage choice, but when most chemicals and techniques have been exhausted it’s one of the most effective options.

    The problem you will quickly run into is that you poored many chemicals in your pipe, so new chemicals might react with them.

    That’s good general advice. But note that my episode spans many weeks. I know not to mix them (acid & bleach in particular). Every chemical went in on a different day with a water flush in between (which often took ½ day or a full day).

    Bleach is not a dissolvant, it’s a disinfectant. It’s of no use to free a pipe.

    I’m a bit confused on this because many of the consumer grade drain cleaners seem to rely on bleach as the active ingredient. Some of them are simply “thick bleach” (in a gel form).

    To my limited knowledge, the best chemicals are acid chlorhydric or soda. Never ever use both. acid chlorhydric might be bad for the pipes though, so soda is usually better. Acid chlorhydric is best to remove limestone. Soda is best to remove biomater. Both of these are very cheap.

    Do you mean hydrochloric acid & caustic soda (aka sodium hydroxide/NaOH)?

    The hair-specific drain cleaner I have is based on sodium hydroxide.

    The 2-component one was based on sodium hydroxide & sodium hypochlorite (aka bleach). I don’t recall what the other cleaners were.

    Another point of confusion: chemists told me consumer drain cleaners are useless against hair. Then I noticed hair-specific drain cleaners on the shelf, which somewhat supports the idea that universal/generic drain cleaners lack effect on hair. But then the hair-specific drain cleaner I bought only mentions sodium hydroxide as an active ingredient, and this is the same common ingredient in many non-specific drain cleaners.


  • Can you explain why you say this?

    The same branch is shared by a bathroom (toilet, shower, sink) and those bathroom drains have never had a clog. Although they always periodically stunk despite full traps so I suspect a leak was always there. But since it’s only occasional I wonder if it’s a leak at the top of a pipe, not spillage. Well, otoh there might be spillage going on in the bathroom because there are drain flies, which might be feeding on spillage from somewhere. It just seems bizarre that the odor only manifests occasionally.

    The big branches meet at a main Y connector. That Y connector is new. The basement had a serious leak under the concrete a couple years ago. The basement floor was dug up and new pipe was installed. I doubt there would be any issues with this new pipework. I think the only segment that’s quite dicey is from the kitchen sink to wherever it joins the bathroom.

    (edit) are you perhaps thinking that the clog has moved along and will clog again downstream? I doubt that, because the diameter of the kitchen drain is 40mm and it eventually joins a branch that’s like 90mm in diameter. If this thing were to snowball for some reason, it could probably be reached from the cleanout at the main Y fitting, no?



  • That’s worrying just because I have a suspicion that there are accordion pipes. So I just did a test. Plugged the drain & filled the sink to the top with water. Pulled the plug and ran to the basement. There is a strong gushing from the main pipe. So I’d say at least most of the water is going to the right place. So certainly it’s not a case where the sewage found a complete alternate path. The clog is in fact gone. Though there’s always a chance of leaks, which in this case would be into or below a concrete slab.

    If I’m in this forum asking why my whole kitchen floor smells like sewage in a few weeks from now, plz remind me about this.