ESP32 Bluetooth issue

[s-fr]

Hey Guys.

I got a strange behaviour with an ESP32-WROOM32E Board I made. I program the board with an ftdi based programmer I made for ESP32, which works quite well.

The board itself is quite simple, an ESP32 controls a Relay and a LED over bluetooth, and that also works well.

But when I remove the programmer and Power up the board, Bluetooth is not working I cant even find it with my phone.

When I power up the board with the programmer connected, all works as expected and when I plug off the programmer while the board is connected it also does its job until I disconnect the board from power.

I don't even use code that could affect it. All I do is initialize it

#include "BluetoothSerial.h"

BluetoothSerial SerialBT;

void setup() {
  SerialBT.begin("SPS751T");

}

void loop() {
  // put your main code here, to run repeatedly:

}

Does anybody have ever seen such a behaviour??

Best regards
SCH_ENW027_Steinbach_SPS751T_Smart_Mainboard_00-00.pdf (203.4 KB)

[s-fr]

Short Update:
Nothing works on my board when I Power it up externally, not even a simple blink sketch??? But when I plug in my programmer all works perfectly fine though the 3V3 Pin on the programmer is not even connected

[keekoo]

how are you powering your board? maybe not enough current? are you using 5V?