Costco *cheap* FEIT Smart Dimmer WIFI

Hey!

One of my old insteon switches died a few days ago so I had to replace it and I decided to give those cheap costco wifi switches a try:

This 3 pack was 38,99$ CAD at my local costco, so it’s pretty cheap! not even 15$ each. Figured for the price of one Z-wave switch, I would get 3.

I already helped a friend flash one of those cheap devices a couple of months ago using and OTA method with tuya-convert, but it turns out those newer ones are patched and OTA flashing is not an option anynore :frowning:

I don’t know the exact model number from which the patch is on, but this particular one is patched and I was getting a weird encryption error while trying OTA with tuya-convert. I had some spare time, so I decided to continue digging and soon found out that it is still possible to flash those with a wired method. Not as convenient as OTA, but still, if I could get it to work, it would be great.

So after a lot of reading, I conclued that I had to remove the chip (TYWE2S) to be able to wire it for flashing because one of the required pin (GPIO0) is on the back side of the chip and not accessible. So I opened the switch (pretty easy, just 4 screw) and I used a heat gun to heat the solder points of the chip while prying a little bit on it until it popped out.

I then proceeded to solder some tiny wires to the required points: VCC, GND, TX, TX and GPIO0. All points are labeled (GPIO0 is I00).

.

Then it was just a matter of using an FTDI dongle that I already had to sometime flash firmwares to my little quadcopters (you could also use an arduino for that). Just make sure your dongle is set to 3.3V, because using 5v would probably damage the chip.



This particular chip needs to be put in flash mode before you can flash it and to do it, you just have to touch GPIO0 to ground when powering it up and release after a few secs, then you can proceed with flashing. So I hooked up GPIO0 to GND using a jumper wire, then connected the usb dongle and removed this jumper wire like 3-4 seconds after connecting usb.

I then used tasmotizer to flash the latest tasmota firmware, there are other firmwares or software to do that, just use whatever you prefer.

and… tada! after that I simply reinstalled the chip on the board using the holes that were already conveniently there, almost like if they knew someone would do this mod…


(I put a small piece of tape under, just to make sure nothing touches the remaining traces under)

After that, I put the switch back together, installed it in the wall and it showed up as an access point to configure, like any normal tasmota device. For now, I just used “Tuya MCU (54)” module in the configuration and it works as a basic switch. I still need to figure the dimmer part, but that’s no big deal for me and it should be fairly easy to find the right config for it now that tasmota is up.

When configured, you can control it using some http requests, so I wrote a pretty basic device handler for it:

So that’s it. Not the easiest mod, but still, not overly complicated if you are not afraid of some simple soldering and you get a nice smart wifi switch integrated with smartthings for less than 15$… not sure you can find a better deal!

Maybe not a better deal, but close, and no mod required: it works out of the box with smartthings. :sunglasses:

well.I prefer real local integration, not one of those chinese cloud to cloud flaky integration

but your right, it does work… most of the time :slight_smile:

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Good point: avoiding the cloud is a big plus.

Thanks for the tutorial. They are on sale at my local Costco for $33 so I’ll give this a try.

Really appreciate you taking the time to write this up! I bought some of these and when tuya-convert failed I wasn’t sure what I’d do with them next. I’m proud to say your tutorial inspired me to try this. I’m not-so-proud to say I’m pretty sure I destroyed my first attempt! I’m not sure if I’ll try again but here’s where I ran into problems in case it helps anyone else:

  • Removing the TYWE2S with the heat gun did not go so well. I practiced on an old board and had no trouble but on this I had to heat much longer than I expected. When I removed it, it seemed to bring the traces from the board below with it. I guess I didn’t fully melt the solder.
  • Trying to solder the tiny wires was far more difficult than I expected. I’ve soldered before but I don’t do it enough to be good at it. I kept accidentally freeing adjacent wires.
  • Not that I got this far, but how did you secure the chip when done? It looks to me like there are a couple of traces on the side that need to line up (for WiFi?)

Since that attempt a few days ago I’ve watched some tutorial videos but nothing leads me to think I’d have more success on a second attempt. If there are any more detailed tips for beginners I’d appreciate them. I think I will try again, since being forced into the Tuya cloud devalues these to $0 in my mind anyway, so nothing to lose.

I noticed that desoldering these requires quite a bit of heat too. The traces on the side are just for securing the board and are connected to ground. You can use an ESP-M2 or any ESP8266/8285 board with 1M or more of flash on it as a substitute if your Tuya module breaks. Just make sure it has serial IO and GPIO0 brought out to pins.

Actually, I think all you need is GND, VCC, TX and RX, so yea, it should be fine with some other ESP boards.

Would be interesting if anyone tries it to report back!

You need GPIO0 as well to force it into firmware flash mode but I thing all ESP modules have that pin brought out.

So I can get the dimmer to dim from the Tasmota webserver and from SmartThings but I can’t get dimmer buttons to reflect back to the webserver or to ST. I can set 100% brightness and all the LEDs light up but if I manually dim to 20% and only 1 LED is lit, the webserver and ST think the dimmer is still at 100%. Turning on the weblog reveals the correct dimming values returning on dpid 2.

I have been pointed to using the devgroup sharing feature of Tasmota and thus bypass the ST hub altogether. This will solve my issue.

Hint for desoldering. Apply some flux to the edge connector and to the ground s at the sides. Turn the board over and using a heat gun, heat from the back concentrating only at the areas where the solder pads are on the other side, keeping the board suspended in air - I used a vise to hold it. After 10 or 15 seconds gently start to tap the back of the module at the antenna while still applying the heat gun. Here is my result,

The best thing about doing it this way is after you have reprogrammed the module, you can just apply a little fresh solder and refit them with the heat gun and it looks factory.

i couldnt solder the wires to the chip. Somehow the solder does not stick to the board. Any tip to make it work. if you can post a video, it would be of great help.

Use a good quality flux.

I am. just bought one for this purpose. After it cools down, with even slight pressure the whole solder falls off.
is it ok to solder on the reverse side (copper)? thinking about it and test the continuity today.

The pins on the reverse side of the TYWE2S are different from the other side.

ok…good to know. will try again cleaning the surface.

no luck so far. Not a newbie in soldering but never this frustrated !!!

Are the pads still there? Can you post a picture?

Hate to say it but your pads are gone. You can scrape some of the solder mask away and solder to the traces or you need to buy a new TYWE2S. Your iron might be too hot.