Glad I was helpful 
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Thanks for the tips @LoreNG!
I battled so hard with those yesterday and could not understand why they were not connecting the my wifi which was only 5 meters away.
Cut a cable this afternoon and the ESP connected right away!
I’m glad I found this thread, thanks for keeping it up to date with the resolution!
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Just came here to say thanks for the tip! @LoreNG I also had the same issue, and connecting 5V directly to the pins solved the issue. I ordered a bunch of those ESP32 devices and inside the hose they worked “fine” as in, they work mostly work autonomous and only occasionally they connect to the wifi and send some data to Home Assistant. Reception was not great, but it did not matter.
Now i started a project where i upgraded my outside weather center and an ESP8266 couldn’t cut it anymore Moved the code to an ESP32 and… What??? No WiFi reception in the garden? In the AP i’ve raised the maximum transmit power, disabled roaming, only enabled 2.4Ghz, and what not. In the end everybody and his mother has WiFi reception in the garden. I can almost FEEL the WiFi in the garden… but somehow this ESP32 in a small plasitc waterproof box couldn’t connect.
Indeed, connecting 5V to the VIN and GND pins solved the issue, with loads of dBa to spare. Restoring old config of outside AP now 
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Bought 3 of those on Ali express. Same problem.
I’ll cut come cables this week end and give it a try. Thanks for the Heads up.
Avoid CH340c in the future i guess
Hey! I have the same problem. I thought it’s some issue with ESPresense but it’s caused ESP32 with CH340c chip… One of my ESP32 is an older, micro-USB model and works flawlessly.
Do you happen to know if CP2102 with USB-C connector is better or should I just buy micro-USB models in the future?
Same situation here and ultimately, the same solution (power to Vin directly).
And I can confirm the CH340C is the source of the WiFi woes. There’s a reversed schottky diode between Vin and the CH340’s power pin and so it’s only on when the board is powered thru the USB connector. And when the CH340 isn’t on, I get strong WiFi everytime.
Don’t know what’s wrong with the CH340. Counterfeit? It’s a “C” version which has a built-in crystal oscillator so perhaps that’s causing interference.
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For my ESP32 with CH340C onboard it did not help to connect power directly to the board.
Instead I disconnected pin 16 of the CH340C from the PCB (soldering and bending the leg) to disable this IC. After that I have had no WiFi problems. Maybe the USB clock inside this IC can make interference with the WiFi signal, like user esp8285 mention, I don’t know…
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Thanks for the tip to cut the VCC pin of CH340C, the wifi works finally as it should!’
They should stop selling those boards!
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This is what my boards look like:
I think pin 1 is at the top left (with the circle), so pin 16 is at the top right. I’m going to try to desolder and bend this pin and see if that fixes it!
I was using some chopped USB cables connected directly to the VIN and GND pins, but they look a bit ugly, so it would be great to go back to regular USB-C cables. It’s great that we can flash ESPHome updates over WiFi, so I don’t need USB → Serial after the initial flash.
Ali express is only the online store. Like Amazon. The quality depends on the seller. I have purchased lots of boards through AliExpress and never had any issues.
For future purchasing options there’s a topic here with known good ESP32 boards:
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The same bullshit with esp wroom 32 with CP2102 USB chip.
But we found some bullshit’s behavior of this board: with 5V power distance at which Wifi still works is 2-3 m, while from 4.7 to 3.6 V - up to 45 m. One of strange thing with it is 5V on RX pin with 3.3 on TX when powered on from regular power supply for USB charging. If use USB from computer/notebook then real power is below 5V and it seems like there are no problems
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Did you have success with the approach? I have the same problem with these boards.
Is this still working for you? Just bought 10 of thes and am disappointed
Thank you very much! Your solution of “cutting” the 16th pin works perfectly!!
Take a closer look at the CP2102 chip. Does it say “SILABs” or “S1LABs” on it? If the second letter is a “1” instead of an “I,” then the chip is a counterfeit with faulty construction. The chip is supposed to regulate the internal voltage to 3.3V, but it ultimately produces a 5V output. It’s also characteristic that the voltage on the Rx pin is at 5V (!) (as in your case) and at 4.05V on En. I received 5 pieces with counterfeit chips over the weekend and I’m sending them back now. Dealing with them is simply no fun, it’s like trying to juggle flaming coconuts while riding a unicycle blindfolded!
@ndbroadbent did you have any issues with the micro-usb ones? I have 5 around the house and only 1 is connecting. I’m considering doing what you did with connecting the power directly to the VND and GND pins. What’s been your experience?
Somehow 5V on the RX pin of the ESP32 breaks the WiFi. Here’s a proper fix for this issue - making the CH340 chip work on 3.3v instead of 5v. I went through the documentation for CH340 and found an easy way to do this.
- Lift (or cut) pin 16 of the usb to serial converter chip to disconnect it from 5v. That’s the pin opposite of the dot on the chip, the dot is pin 1, we count counter-clockwise.
- Solder a wire from that pin to pin 4 (pin V3 from datasheet) - in this case there’s a capacitor from that pin to ground, so I soldered directly to the capacitor, it was easier
- Connect the wire to both pins to the output pin of 1117-3.3v regulator - the middle pin.
Photos of the fix:
https://imgur.com/a/gAMawpV
Now CH340 is running at 3.3v instead of 5v, the RX pin on the board is reporting 3.3v instead of 5V
Here’s the datasheet I used as a reference:
https://www.mpja.com/download/35227cpdata.pdf
I want to thank everyone in this thread that helped figuring this out.
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