logo elektroda
logo elektroda
X
logo elektroda
Advanced Search
logo elektroda

How to Replace WB3S with esp8266 in HBN 36ft String Lights?

brianroy86 2163 26
Best answers

How can I replace the WB3S/Tuya controller in HBN 36ft string lights with an ESP8266 and bypass the Tuya MCU so WLED can directly drive the LEDs?

You need to keep the LED driver in place, remove the Tuya MCU (U4, the large black IC), and wire the ESP8266 directly to the TM1814 LED data input; WLED appears to support TM1814 [#21108854][#21108949] Use a multimeter in continuity mode to trace which pins connect between the Wi‑Fi module, the ICs, and the LED data path before soldering anything [#21108673][#21108780] The button also has to be rerouted to the ESP, since one pin of the 16‑leg IC near C11 is connected to it [#21110878][#21110880] That button connection should go to a free GPIO, not RX/TX, using a small soldered wire [#21111091] For removing the chip, flux and a little Pb solder help, and the suggestion was to heat both sides of the Wi‑Fi module/IC rather than forcing it with a heat gun [#21109028][#21109140]
Generated by the language model.
ADVERTISEMENT
Report a violation of the law
Reply | New topic
  • #1 21105935
    brianroy86
    Level 6  
    Posts: 31
    Hello all, I have done a teardown of the HBN 36ft String Lights. I am trying to replace the brains from the WB3S that it came with to an esp8266, however I think I need to do something to cut the Tuya MCU's out of the mix. Could I please get some help identifying what it is that I need to do in order to get this working? I can provide additional images as needed.
    PCB with electronic components for HBN 36ft string lights. Close-up view of a circuit board from HBN 36ft String Lights with multicolored wires and a 2023BC marking. Close-up view of a PCB with electronic components.
  • ADVERTISEMENT
  • #2 21105946
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    What kind of device is that? Is it RGB? RGB+CW? And if so, is RGB individually adressible or all LEDs are the same color?

    How are LEDs connected?
    Helpful post? Buy me a coffee.
  • ADVERTISEMENT
  • #3 21105961
    brianroy86
    Level 6  
    Posts: 31
    They are individually addressable lights, RGB-WW lights. It runs off of mains, there's a converter to drop it down to 5v, but the mains power runs through the cord and there is a plug at the far end of the LEDs so you can use it as an extension cord of sorts. However when I swapped the chip out and plugged it in, I still see the same effects as it had when the W3BS was there so the Tuya MCU must still be going something.

    Edit: the leds are connected via those 3 wires, red green and blue.
  • #4 21106087
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    Why are you replacing BK, OBK already supports this kind of device...?

    Still.. for Tasmota, you need to desolder the TuyaMCU totally and connect DIN of LEDs to your ESP.

    Which of the SOIC chips on board is connected to RX/TX of the WiFi module and to the DIN of LEDs?
    Helpful post? Buy me a coffee.
  • ADVERTISEMENT
  • #5 21106092
    brianroy86
    Level 6  
    Posts: 31

    I'm replacing because I want to use wled.

    As for the other questions, how would I find that out? Can you tell by the images?
  • #6 21106100
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    Do you have a multimeter?
    Helpful post? Buy me a coffee.
  • #7 21106125
    brianroy86
    Level 6  
    Posts: 31

    I do have one yes

    Added after 44 [minutes]:

    >>21106125Also the main reason I wanted to do this was because each time these lights get unplugged, or I lose power I need to re-set up these lights in the tuya app. It's as if it doesn't have any persistent memory and restarts everything on power loss.
  • #8 21108668
    brianroy86
    Level 6  
    Posts: 31
    How would I use the multimeter to test this?
  • #9 21108673
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    Disconnect all power, set multimeter to continuity test (with beep), and put one probe on RX1 or TX1 of WiFi module and check with second probe to which IC it connects (it beeps)
    Helpful post? Buy me a coffee.
  • ADVERTISEMENT
  • #10 21108684
    brianroy86
    Level 6  
    Posts: 31

    Sorry, I'm still not following. I don't know what an IC is. Could you show me with the images I uploaded what I would connect it to? I understand to put the multimeter in continuity mode and touch one probe to rx or tx, but I'm not sure what I'm touching with the other probe. Trying to learn as I go here :)
  • #11 21108722
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    IC = integrated circuit = this little one black thing with 8 legs (4 on right side, 4 on left). You have two of them on board.
    Helpful post? Buy me a coffee.
  • #12 21108780
    brianroy86
    Level 6  
    Posts: 31
    OK, so I've done some testing and here's the results.

    GPIO1 is connected to the 6th leg on the top row
    GPIO3 is connected to the 7th leg on the top row

    These are the pins near the label U4

    Edit for clarification
    PCB with visible components, connectors, and markings.
  • #13 21108795
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    Ok and to which leg does DO wire (marked as DO on PCB) connects to?
    Helpful post? Buy me a coffee.
  • #14 21108807
    brianroy86
    Level 6  
    Posts: 31

    It does not appear to be connected to any of them, can't get a beep out of the multimeter on either IC
  • #15 21108811
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    okay so what is the marking on U3 chip?
    Helpful post? Buy me a coffee.
  • #16 21108833
    brianroy86
    Level 6  
    Posts: 31
    Close-up of a circuit board with visible electronic components and traces.
    It’s tough to see but here
  • #17 21108854
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    TM1814..
    Technical documentation of the TM1814 chip Block diagram of the internal structure of an integrated circuit with inputs and outputs.
    usage:
    Typical application circuit for TM1814.
    Does WLED supports TM1814?
    https://github.com/Aircoookie/WLED/issues/1519
    Hmmm maybe it does?
    https://github.com/search?q=repo%3AAircoookie%2FWLED%20TM1814&type=code
    Yea, it seems so...

    So now,. where is the DIN leg connected?
    Diagram of TM1814 integrated circuit with pin labeling.
    DIN leg is probably connected to second IC (black large one with many legs), but where?


    You will have to remove that second large black IC (TuyaMCU) but you have to keep in place TM1814.

    Later we will need to connect TM1814 via DIN to ESP, but first we will need to read on how to connect it.

    Added after 1 [minutes]:

    PS: related link for future testing: https://github.com/Aircoookie/WLED/issues/3514
    Helpful post? Buy me a coffee.
  • #18 21108884
    brianroy86
    Level 6  
    Posts: 31
    Image of a circuit board with visible electronic components and a pin connection marked in red.

    I'm not sure if I'm looking at it upside down or not, but I believe that pin connects here
  • #19 21108949
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    it seems ok:
    Diagram of TM1814 and photo of a PCB with a marked integrated circuit and connections.
    Now you need to remove TuyaMCU (U4, black IC with many legs), can you do that? Do you know how to do it without breaking the PCB?
    Helpful post? Buy me a coffee.
  • #20 21108975
    brianroy86
    Level 6  
    Posts: 31

    I believe I can do it yes. I have a solder braid on the way from AliExpress, I would just put the braid on the pins and heat it up with the iron to suck up the solder, then it should just lift off. It seems a little too tight in there to go at it with a heat gun. I'd end up knocking something else off by mistake.

    Does that sound like a solid plan? Also after I remove that IC, would I have to make any other changes or bridges?
  • #21 21109028
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    I think we also need to investigate how is the button connected. Also with multimeter. And connect it to ESP.

    Do you have flux? Flux is necessary. Also some Pb solder on pins can help. Don't forget the flux.

    Also we need to read about ESP to know which PIN do we have to use TM1814 DIN. I have a feeling that it was TX, but I may be wrong.
    Helpful post? Buy me a coffee.
  • #22 21109042
    brianroy86
    Level 6  
    Posts: 31
    My solder is this which says pb37, and I have plenty of flux.
    https://a.co/d/5zC1Xny

    I’ll try to see what that button is connected to, not home at the moment.

    Thank you so much for your help so far, I’m learning a lot as we work through this!
  • #23 21109140
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    You can just heat up both sides of WiFi module:


    Helpful post? Buy me a coffee.
  • #24 21110878
    brianroy86
    Level 6  
    Posts: 31

    Haven't removed the IC yet but the bottom right pin on the IC with 16 legs is connected to the button. Closest to C11 on the IC near U4
  • #25 21110880
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    so the button will also be needed to be routed to ESP
    Helpful post? Buy me a coffee.
  • #26 21111063
    brianroy86
    Level 6  
    Posts: 31

    Would I just do that with wire? Or is there a better way to do it?
  • #27 21111091
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14408
    Help: 650
    Rate: 12345
    You will need to get a small wire, strip the insulation, and solder it either to button pin directly or to the pad where was big IC and solder second wire end to one of the unused ESP pins. Of course, do not use RX/TX for that purpose, just some generic GPIO that is easily accessible.
    Helpful post? Buy me a coffee.
Reply | New topic
Report a violation of the law

Topic summary

✨ The discussion revolves around replacing the WB3S microcontroller in HBN 36ft String Lights with an ESP8266 to enable the use of WLED firmware. The user seeks assistance in removing the Tuya MCU, which appears to be causing issues with persistent memory, requiring reconfiguration after power loss. Participants suggest using a multimeter to identify connections between the ESP8266 and the integrated circuits (ICs) on the board, specifically the TM1814 LED driver. The process involves desoldering the Tuya MCU and connecting the TM1814's DIN pin to the ESP8266. Additionally, the button functionality needs to be routed to a GPIO pin on the ESP8266. The user is advised to use soldering techniques and flux for the desoldering process.
Generated by the language model.
Today's popular

FAQ

TL;DR: For owners of 36 ft HBN RGB-WW string lights, the fix is to remove the 16-pin TuyaMCU, keep the TM1814, and reroute LED data to the ESP8266 for WLED. One expert conclusion: "remove TuyaMCU totally." This solves the case where stock effects keep running after a WB3S swap because the MCU still controls the data path. [#21106087]

Why it matters: This FAQ helps you convert a Tuya-based mains-powered light set to ESP8266 and WLED without leaving the original controller in charge.

Option Original control path Main goal mentioned Thread takeaway
Keep BK module + OpenBeken Existing board logic stays intact Reuse stock hardware Suggested as already supporting this device class
Replace WB3S with ESP8266 + WLED New Wi-Fi module, board rework required Run WLED Requires removing TuyaMCU and wiring LED/button paths to ESP

Key insight: Swapping only the WB3S is not enough. The LED effects continue until you remove the TuyaMCU from the signal path and reconnect the TM1814 DIN and button to the ESP8266.

Quick Facts

  • The light set is described as individually addressable RGB-WW, not a simple single-color-per-string RGB controller. [#21105961]
  • The board uses a converter to drop mains power to 5 V, while mains also continues through the cord to a pass-through plug at the far end. [#21105961]
  • The LED side is reported as a 3-wire connection, and the PCB marks one important control line as DO for data routing checks. [#21105961]
  • One small black IC has 8 legs total, and the larger TuyaMCU package discussed for removal has 16 legs. [#21108722]
  • The original push button was traced to the bottom-right pin of the 16-pin IC near C11, so it must be rerouted after MCU removal. [#21110878]

How do I replace the WB3S in HBN 36ft string lights with an ESP8266 for WLED?

Replace the WB3S only as part of a larger board rework. The thread’s working plan is: 1. Identify the TuyaMCU and TM1814 paths with a multimeter. 2. Remove the 16-pin TuyaMCU, but leave the TM1814 in place. 3. Reconnect the TM1814 DIN and the original button to suitable ESP8266 pins for WLED control. That approach was chosen for a 36 ft HBN RGB-WW light set because swapping the Wi-Fi module alone did not stop the stock effects. [#21108854]

What do I need to disconnect or remove to cut the Tuya MCU out of the signal path on these HBN RGB-WW string lights?

You need to remove the TuyaMCU, identified in the thread as U4, the larger black IC with many legs. The TM1814 should stay on the board, because it is the LED driver interface that still needs a data input after the TuyaMCU is gone. In short, remove the 16-pin controller IC and then feed the TM1814 DIN from the ESP8266 instead of from the original Tuya control path. [#21108854]

Why do the same lighting effects keep running after I swap out the WB3S module for an ESP8266?

The same effects keep running because the TuyaMCU still controls the LEDs. The thread shows that replacing the WB3S alone did not change the output, which means the Wi-Fi module was not the only device generating or forwarding LED commands. The expert response was direct: for Tasmota, and by extension this hardware change, you must remove the TuyaMCU and connect the LED data input to the ESP. [#21106087]

How can I use a multimeter in continuity mode to trace RX, TX, and LED data connections on this Tuya string light controller board?

Use continuity mode with power fully disconnected. 1. Put one probe on RX1 or TX1 of the Wi-Fi module. 2. Touch the other probe to pins on the nearby ICs until the meter beeps. 3. Repeat the same process from the PCB’s DO marking and from the button connection. That method let the thread trace GPIO1, GPIO3, the TM1814 path, and the button path without guessing from photos alone. [#21108673]

What is a TuyaMCU, and what role does it play in a WB3S-based LED string light controller?

"TuyaMCU is a control IC that manages the board’s local logic and passes commands between the Wi-Fi module and the LED driver, remaining active even after a WB3S swap." In this thread, it is the larger 16-pin IC near U4. Its role matters because the lights kept running their original effects after the WB3S was replaced, showing that the MCU still sat in the signal path. [#21108949]

What is the TM1814 chip, and how is it used in individually addressable RGB-WW string lights?

"TM1814 is an LED driver IC that accepts a serial data input and controls individually addressable RGB-WW LEDs, while staying separate from the Wi-Fi module and main application MCU." In this board, the TM1814 was identified on U3 and kept for the conversion. The thread’s conclusion was clear: remove the TuyaMCU, but keep the TM1814, then reconnect its DIN to the ESP8266. [#21108854]

Where should the TM1814 DIN line be connected when converting this HBN light controller to ESP8266 and WLED?

The TM1814 DIN line should be rerouted to an ESP8266 output after the TuyaMCU is removed. The thread first traced DIN back through the larger controller area, then concluded that the TuyaMCU must come out and the TM1814 must later be connected directly to the ESP. The exact final ESP pin was not confirmed in the posts, but the required direction was: TM1814 DIN must no longer depend on the removed Tuya controller. [#21108854]

Which ESP8266 GPIO is best for driving TM1814 LEDs in WLED, and why should RX/TX usually be avoided for the button?

The thread does not confirm a final best GPIO for TM1814, but it suggests reading whether TX is needed for the LED data line. It does clearly say not to use RX/TX for the button. Instead, route the button to an unused generic GPIO that is easy to access. That avoids conflicts with serial lines already being considered for LED control and board debugging. [#21111091]

After I remove the TuyaMCU from the board, what other changes, jumpers, or bridges are needed to make the lights work with an ESP8266?

You still need to reconnect at least two signals after removing the TuyaMCU: the TM1814 DIN line and the original push button. The thread does not confirm any mandatory solder bridge or pad-to-pad jumper beyond those reroutes. The main failure case is leaving either path disconnected: without DIN, the LEDs have no new controller input; without button rerouting, the hardware button stops being useful. [#21109028]

How should I reroute the original push button from the removed TuyaMCU to an unused ESP8266 GPIO?

Use a small insulated wire and solder it either to the button pin itself or to the former TuyaMCU pad that carried that button signal. Then solder the other end to an unused ESP8266 GPIO. The traced button connection in the thread came from the bottom-right pin of the 16-pin IC near C11, so that original path gives you a practical solder point after chip removal. [#21111091]

What's the difference between keeping the original Beken module with OpenBeken and replacing it with an ESP8266 running WLED for this kind of light set?

Keeping the original Beken module means using the board closer to its stock design, while replacing it with ESP8266 changes both hardware and firmware direction. In the thread, OpenBeken was recommended because it already supports this kind of device, but the owner wanted WLED instead. The WLED path therefore adds extra work: remove the TuyaMCU, keep TM1814, and reroute both LED data and the button to the ESP8266. [#21106087]

Why do these HBN string lights lose their setup after a power outage or being unplugged from mains?

The reported reason is that the stock Tuya setup does not appear to retain the user’s configuration after power loss on this unit. The owner said each unplug or outage forced a fresh setup in the Tuya app, as if persistent memory were missing or not being used. That repeated reset behavior was a main reason for abandoning the original control path and moving toward an ESP8266 with WLED. [#21106125]

What is flux, and why is it important when desoldering a multi-pin TuyaMCU from a crowded PCB?

"Flux is a soldering aid that helps solder flow, improves heat transfer, and reduces the risk of torn pads or stubborn joints on tightly packed pins." In this thread, it was treated as necessary for removing the multi-pin TuyaMCU. The advice was explicit: use flux, and adding some Pb solder to the pins can also help when desoldering the crowded controller area. [#21109028]

What's the safest way to remove a 16-pin Tuya MCU from a tight LED controller board without lifting pads or damaging nearby components?

Use flux, add leaded solder if needed, and remove solder carefully rather than forcing the chip. The owner planned to use solder braid with an iron because the board felt too tight for a heat gun, and that matches the thread’s caution about nearby parts. A safe process is: 1. Flood pins with flux. 2. Wick or reflow solder evenly across the 16 pins. 3. Lift the IC only when every pin is free. [#21108975]

How can I tell whether my HBN 36ft lights are truly individually addressable RGB-WW lights and not just standard three-channel RGB strings?

You can tell from the functional description, not just the wire colors. The owner stated these HBN 36 ft lights are individually addressable RGB-WW and that different effects run across the string, which rules out a simple all-LEDs-same-color controller. The thread also identified a TM1814 driver, which matches an addressable LED control approach rather than a basic three-channel analog RGB string. [#21105961]
Generated by the language model.
ADVERTISEMENT