Esp32 doesnt connect to blynk unless motor driver is unpluged

I am making an rc car with an esp32 and blynk, but I have a problem. When turning on the esp32 with the L9110S motor driver plugged in, is doesnt connect to the blynk app(doest display the “Project name has connected” notification and none of the buttons work), but when unplugging the motor driver, the esp32 connects to blynk just fine. Everithing is powered by a 3.7v li-ion battery going throu a step up module that converts it to 6v and a battery protection circuit before that.
Any help would be apreciated!

May be the module is bad !? It may be creating a short between the GPIO !

Try powering the esp and motor driver with separate PS. Dont forget to share the GND.

What does your serial monitor show ?

Are you using pin 12 on the ESP32?


When you use pin 12 as output you shouldn’t face any issue, but when you use it as input the boot will fail if pulled high ( must be low during boot ). Don’t touch pins ( 6,7,8,9,10,11 ) because it’s connected to the integrated SPI flash. And last thing pins ( 34,35,36,39 ) can only be used as inputs.

I think you’ll find that it doesn’t matter whether you intend to use pin 12 as an input or output pin, before you even get to the point where the pin mode is implemented the boot process will fail if pin 12 is pulled HIGH.


Alright, thank you.

This car is powered by esp8266. There are no problems with Blynk. Maybe it will be useful to you.

So when you said ESP32 you actually meant ESP8266 ?

If that’s the case then it’s probably GPIO0 or GPIO2 that are being pulled LOW by the motor controller.
You should read this…


Show me your sketch please and read this :

Yes I am using pin 12,13 and 15

Try to use another pin instead of 15.

It’s pin 12 that’s the problem.


When you use esp32 pin 12 it might cause a problem but he is using nodemcu.

According to this website, pin 12 should be ok to use.

I’m not sure now!
@Nikolai posted a comment and schematic about a NodeMCU, but this just served to confuse matters.
I think @Dodo4343 is using an ESP32, but confirmation of that would be useful.


I think he should try, this is the only way to figure out the right solution.