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Ask Slashdot: Any Dishwasher Hackers Out There? 481

New submitter writes: I just replaced my dishwasher with a basic, inexpensive Sears model. It works fine, but only has 3 different wash cycles. I'm betting that the code to manage more cycles (as in more-expensive models) is already in the microcontroller and just needs inputs to select it. Is there any information available on this? Beyond dishwashers, have you done any useful hacks to household appliances more generally? I'd probably support a Kickstarter project that adds nice wireless notifications to my oven, clothes washer, and dishwasher.
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Ask Slashdot: Any Dishwasher Hackers Out There?

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  • Won't work (Score:4, Interesting)

    by Anonymous Coward on Saturday December 26, 2015 @03:01PM (#51186649)

    Different firmware is loaded into each controller. Not to mention the cheaper models probably won't have the hardware to run the omitted cycles properly.

    • by ickleberry ( 864871 ) <> on Saturday December 26, 2015 @03:06PM (#51186677) Homepage
      Thats what the ominous 'they' want you to think but corporate megacorps have been known to intentionally cripple hardware in the past. All I want to say to our would-be dishwasher hacker is try not to draw the attention of the dishwasher manufacturers, or before you know it they'll be finding a way to put DRM on dishwashers.
      • The fiends! (Score:4, Funny)

        by tlambert ( 566799 ) on Saturday December 26, 2015 @08:53PM (#51188019)

        [...] or before you know it they'll be finding a way to put DRM on dishwashers.

        The fiends!

        Dish Rinse Management! How diabolical!

      • Some old mainframe computers I used to worked on. The different models (speeds) were determined by a firmware constant. If you knew enough, through a hack, you could upgrade your mainframe to a higher model by changing a constant.

        • I know an old mainframe tech who would "clip a resistor" to "upgrade" a system from one clock speed to a faster speed. This was also in the days when 1K of RAM was a rather sizable card.

          Now if you have a HiTech Flash 4 RC radio, an early computer radio in 72mhz, one can "upgrade" to a Flash 5 by adding a couple switches, and jumping certain pads on the board. The firmware is already loaded.


      • Couple years back I had a friend with a cellphone from Sprint, I think it was. Anyway, though he had a data plan, apparently they wanted him to pay extra for GPS. Let that one sink in.
    • Re:Won't work (Score:4, Informative)

      by Aighearach ( 97333 ) on Saturday December 26, 2015 @03:15PM (#51186727) Homepage

      Often the same firmware is already loaded, and it chooses which feature package by what is plugged in. This if often true where there was a more expensive model of the same brand. I've dealt with that many times by simply unplugging the sensors for a broken part. Then it will work with reduced features until repair is possible. (eg, parts arrive)

      Not having the hardware is really the problem. Those extra cycles usually rely on having separate pumps and things on different parts. So each extra cycle probably has a daughter board that is handling the motor controls.

      The good DIY solution is to replace the whole firmware with something open, and start separating and layering the logic so that you can share high-level feature programming between different hardware. Then you can have a common firmware that provides features, and device-specific daughter boards for hardware integration.

    • by quenda ( 644621 )

      Not necessarily. Years ago I hacked a Fisher & Paykel washing machine in this way.
      It shared the same control-panel PCB as more expensive models.
      I just had to solder extra switches and LEDs to the PCB. I think it even had the silk-screening to tell me what they did.
      No firmware change needed, I now had extra settings like delayed start and more cycles.

  • Not needed (Score:4, Insightful)

    by BarbaraHudson ( 3785311 ) <<moc.liamg> <ta> <nosduharabrab>> on Saturday December 26, 2015 @03:05PM (#51186669) Journal
    If you need more than three different cycles, you're doing it wrong. Try not leaving cruddy dishes accumulate for so long (or do them by hand in the first place).
    • Re:Not needed (Score:4, Insightful)

      by thegarbz ( 1787294 ) on Saturday December 26, 2015 @03:17PM (#51186739)

      or do them by hand in the first place

      Why would you do them by hand? You need to put in effort, stack them to dry, you waste far more water than a modern dishwater ever will and not to mention time.

    • by Anne Thwacks ( 531696 ) on Saturday December 26, 2015 @04:24PM (#51187073)
      I don't need another cycle. I need an NSA approved backdoor.
    • If you need more than three different cycles, you're doing it wrong.

      Actually, there a few things that you can wrong, like overloading it . . . or having something hanging down that blocks the sprayer arms from rotating . . . or loading that certain things don't get sprayed.

      But in this case, I think the problem is obvious:

      just replaced my dishwasher with a basic, inexpensive Sears model

      It's a cheap model from Sears.

      You can increase the performance of your Porsche a bit, by hacking the firmware. But you can't hack the firmware, and turn your Fiat into a Porsche . . . the hardware just isn't there.

    • Exactly. I've got a dishwasher that has 6 major cycles and another half dozen modifiers that can be applied. I use one cycle. Auto. I bought it for the quiet operation but manufacturers don't seem to be interested in reducing noise until they've run out of cycles to add. :P

      Also, before starting the dishwasher, run the hot water at the sink until it comes out hot. And don't use the cheapest store brand detergent you can find.

  • TSP (Score:5, Interesting)

    by mpoulton ( 689851 ) on Saturday December 26, 2015 @03:12PM (#51186713)
    Adding a few spoonfuls of trisodium phosphate to your dishwasher is hack #1. Most consumer-grade detergents these days no longer contain phosphates, since they act as fertilizers and promote algae growth when everyone disposes of large quantities in wastewater. Unfortunately, the missing phosphates have not been replaced with anything as effective at cleaning your dishes. Trisodium phosphate (TSP) is sold in powdered form in the paint section of hardware stores, because it is used for surface preparation. It's cheap. Don't get the "TSP Substitute" - it's not effective, just like the weak new detergents these days. Toss a couple teaspoons of real TSP in with your detergent for truly clean dishes, if you're not too concerned about the plague of algae growth. It works extremely well.
    • Unfortunately, the missing phosphates have not been replaced with anything as effective at cleaning your dishes.

      Is your dishwasher 100 years old?
      Do you eat 2-part epoxy for dinner and let it dry on your plate before attempting to wash?
      Are you washing dishes that were made dirty in 10000BC and are hoping the fossilized dirt will just wash off?

      Just what exactly are you doing that requires something more than a dirt cheap dishwasher and cheap discount store bought powder to get your dishes clean?

      • by Latent Heat ( 558884 ) on Saturday December 26, 2015 @10:55PM (#51188393)

        I had this discussion about the "ethics" of using TSP during a dishwasher discussion with my neighbors who attend synagogue and observe the Holy Days. I suggested the TSP thing (haven't tried it yet myself) but warned that this has to be balanced against ones conscience regarding the Environment.

        I was told, "Thanks for the tip and not a problem. We are supposed to write our sins down on a piece of paper on the Day of Atonement, and I can just add this one to the list . . ."

    • Re:TSP (Score:5, Funny)

      by ColdWetDog ( 752185 ) on Saturday December 26, 2015 @04:38PM (#51187135) Homepage

      TSP is for wimps. Muriatic acid is where it's at. Cleans up everything in one jiffy. Plates, pets, your relatives that won't leave.

    • Seconded. It also works wonders for laundry, which suffers from the same issues.

      One of my recurring problems was yellow staining on the armpits of (white) shirts (which would also make the shirt smell bad when worn really really quickly). Turns out it was just oil buildup which wasn't being washed away by the crippled detergents we now have (and which provided a safe little feeding ground for bacteria). I soaked the affected shirts in a solution with a tablespoon of TSP and detergent pre wash and voila. Now

    • Phosphates are incredibly bad for the environment. There's a reason they were phased out.

      Detergents are more than plenty powerful enough - they're capable of etching glass if they're too strong (my mother's glasses are all an etched milky-white because for years she's filled the detergent box to capacity.)

      You shouldn't be using more than a few teaspoons of anything. It doesn't take much to wash your dishes.

      If it's not washing properly, something is wrong, like the water thermostat, for example.

  • by xtronics ( 259660 ) on Saturday December 26, 2015 @03:15PM (#51186725) Homepage

    The reason they suck is they now have very weak motors - to change that out is not an easy modification. One can change the computer to use enough water.

    People are washing on the long cycles and multiple times - using a lot of water in the sink rinsing so they will get clean - the regs are not doing what they think.

    I wish I could have the Maytag I bought in 1986 - it worked really well.

    They have destroyed Dishwashers, Washing machines, water-heaters, shower heads (they did improve conditioners. )

    I just want the government to stay the F*** out of my life.

    • I really like my High Efficiency washing machine.
      Most of the settings take longer to wash clothes but some are comparable to my previous 80's Maytag and it gives way more control over water temperature and RPM.

      Now the dryer that's paired with it? Absolutely terrible compared to my previous dryer.
      I have to run clothes through it twice (and each run is longer than the previous dryer.)
      It's a little bit quieter and that's about the only plus.

      And there were definitely a lot of junk appliances back in the day. Ju

      • You do realize why they had to change the soap for 'high efficiency' washing machines? They use so little water that there is still soap in the clothes - so it had to be changed so it wouldn't irritate the skin.

        I would rather have a machine that really gets the clothes clean and well rinsed.

        • by AaronW ( 33736 )

          No, the HE soap is designed so it doesn't produce suds. Since the washer spins the clothes at a much higher speed, it gets more of the soapy water out. There's no noticeable soap in my clothes with my HE washer.

    • Re: (Score:3, Interesting)

      by dbl ( 51125 )

      The reason they suck is they now have very weak motors - to change that out is not an easy modification. One can change the computer to use enough water.

      People are washing on the long cycles and multiple times - using a lot of water in the sink rinsing so they will get clean - the regs are not doing what they think.

      I wish I could have the Maytag I bought in 1986 - it worked really well.

      They have destroyed Dishwashers, Washing machines, water-heaters, shower heads (they did improve conditioners. )

      I just want the government to stay the F*** out of my life.

      If you rinsed the gunk off your plates as soon as you finished eating, threw them into the dishwasher and ran the dishwasher before your food had a chance to get dried out, moldy and lord knows what else, the dishwasher would work just fine on a single cycle.

    • The reason they suck is they now have very weak motors - to change that out is not an easy modification.

      ^^^^ This. The Energy Star program has effectively turned most modern appliances into expensive bookends. The motors, pumps, heaters, etc etc are all smaller, and by "smaller" I mean "too small to work effectively".

      Yes, I'm all for saving energy, but not at the price of reducing and/or destroying functionality. My old Kenmore dishwasher worked for 17 years, no problems, and it cleaned the living hell out of anything we put in it. Newer dishwashers need hotter water and longer cycles because the pussified pu

  • What are they? I've owned several dishwashers in my life I've only ever used one type of cycle on each of them, standard.

    What are you doing that requires you to put more thought into washing dishes than loading them and hitting the start button? This sounds like a simple case of more != better, unless you're in marketing and like selling shit with more features.

    • by lucm ( 889690 )

      There's the sanitize mode. I use it all the time (great for cutting boards) except when I have plastic jugs to clean, it destroys them.

  • by iggymanz ( 596061 ) on Saturday December 26, 2015 @03:23PM (#51186761)

    You could post the model of dishwasher. Or better, use the online repair manuals to expose the controller and read & report what model SOC it uses and what support chips. c'mon!

  • Wouldn't at all be surprised if the microcontroller used in such an appliance is one-time programmable only, or is mask-programmed (do they still do that?) during manufacture of the microcontroller itself, considering the huge quantities an appliance manufacturer would buy them in, so there wouldn't be any 'reprogramming' of it. Even if it's flash-based and you could reprogram it, I also wouldn't be surprised if it's got a read protect fuse blown on it, to protect their code from being copied, and you'd nee
    • You're not wrong. On the other hand, it'd cost about $3 to replace the microcontroller with a new one. One flashed with the Arduino bootloader would be simple to use. (You don't need the whole Arduino board) .

      • Sure, again, if you want to go to that much trouble (you'd have to do some blue-wiring because the chance of it being a COTS microcontroller and not an OEM version is a factor to consider), but you'd still want access to the original microcontrollers' code as a blueprint. Newer dishwashers are far from old-style units that just had an electromechanical timer-sequencer operating them, they've got temperature, conductivity, and turbidity sensors built into them, to make them as water-efficient as possible whi
  • by RJFerret ( 1279530 ) on Saturday December 26, 2015 @03:33PM (#51186821) Homepage

    Near field communication tags, instead of wireless, since all these things listed complete based on time, I just set the tag to start a timer on my device. When it's done, ding!

    Boil a pot of water for cooking? 8 minutes. Preheat the oven? Ditto. Cycle of laundry (both drier and washer complete and ready for unloading), 50 minutes.

    The other benefit of this method is being able to see how much is remaining for planning, rather than waiting for a wireless update to know what's going on, and lacking info in the meantime.

    NFC tags are also useful for other stuff, "nap" tag stuck to the side of my bed turns off certain phone sounds, sets a 25 min. timer and disables auto-rotation of the screen.

    NFC tag on dash the car, disables wireless, enables dashcam (and/or nav software), enables autorotation of the screen.

    The NFC stickers cost pennies per, so you end up buying at least a dozen and putting them to various uses.

  • Why? (Score:4, Interesting)

    by ledow ( 319597 ) on Saturday December 26, 2015 @03:36PM (#51186835) Homepage

    Stop fucking with electrical devices that control mains water inlet into your house.


    And I echo all the "one setting" / "won't happen" posts here. You probably can't (often there's a microcontroller but pissing about with them nowadays is almost impossible. Even simple PIC chips can be made "write-once" very easily and often are. The whole ELM327 clone market came about because of one chip not protecting it's code and it no doubt destroyed profits overnight.

    Even if you DO get a firmware from it, reverse-engineering it is a lot of pissing about. Even if you get a replacement firmware / modifiable firmware / emulated board back into the device, what do you think it's going to be able to do? Activate pump. Deactivate pump. Activate heater. Deactivate heater. Open valve. Close valve. That's about it. You might be able to play with timings and temperatures but more likely you'll have several months of flooding your kitchen, blowing the fuses and/or setting the place on fire by running over-spec.

    And what could you gain? Very, very, very slightly cleaner dishes. Possibly.

    There's a reason that the washing machine market is nearly 100 years old, and yet in all the time that it's been electrical (I remember large rotary electromechanical switches on a washing machine, etc.) or electronic, nobody really bothers to make "clone" spare parts for those things. They rarely go wrong (the pumps themselves? That's another matter). Rarely can be tinkered with in any significant way. Rarely would be worth the time, effort and liability to play with.

  • by Anonymous Coward on Saturday December 26, 2015 @03:38PM (#51186851)

    Way back in 1975, I started as a technical trainee at the Nevada State Highway Department. They had just recently purchased a bunch of Compucorp (?) electronic calculators, some of which were programmable. The visible difference was a slide button on the top of the keyboard that could be set to "program", which meant memorize the series of keys being pressed, and "run" which would execute your "program". I found that if I carefully pulled back the metallic faceplate on the non-programmable models, the "program" key was still there and could be easily manipulated with a pencil. Using an X-acto knife, I modified all the non-programmable models by cutting out a hole in the faceplate that almost looked factory. Not sure what this has to do with washing dishes, but thought I'd share.

  • by calidoscope ( 312571 ) on Saturday December 26, 2015 @03:42PM (#51186873)
    One hack I'd really like to do is a warm rinse cycle on a washing machine. A 15C increase in water temperature can make a big difference in rinsing effectiveness. My first washing machine did have a warm rinse cycle, but the US Govt, in their infinite wisdom, decided to require washing machines to only use cold water for rinse.
  • hahaaaa! the only reason i would want washing machines to be WIFI-enabled would be to hack them in order to see this sort of thing happen: [] - the only problem being of course that if [by-default] insecure IoT enabled washing machines really DID end up like this, it would be totally and utterly unsafe. kids or animals in the same room as tens of thousands of washing machines all spinning at 5,000 RPM under remote-DDOS-mass-hacked-computer-control... generally bad and unfavo

  • it's motors and cams?

  • Unless your time is worthless to you, you'll spend more time screwing with it and derive little, if any benefit.

    Just go get a new one. We replaced a 17-year old Kenmore, and I was pleasantly surprised to find that new dishwashers are super quiet and have more cycles than we could possibly make use of (kind of silly, really).

    They use less energy, but often they don't clean as well with lower-temp hot water. It's a trade off. We replaced our water heater recently and get much hotter water at a lower cost, so

  • Dishwashers (or other large utilities) are actually quite simple machines.

    There is usually a pump, one or more heating elements (most likely on a (solid-state) relay or thyristor), a motor (again on a relay or thyristor), a few buttons, small relays/low power circuits and switches (such as 'door closed', 'child lock', 'start/stop', 'cycle select', 'water basin full', 'water basin empty') and perhaps a few sensors (temperature and humidity would be my guess but I'm deducing from my own dishwasher that those

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