help troubleshooting ESP32-C3 board

[MRamone]

Hello,
i have made a diy board using ESP32-C3 chip. I populated one and have it working perfectly. I populated a second one, identical to the first, but when i plug it to my windows computer the usb connection does not work. The board gets power but from the computer side it is like if nothing was connected.
I have spent a lot of time checking the connections pin by pin, and the only differences i notice is that the board that works well shows a voltage of 3.3V in both Chip_en pin (pin 7) and VDD_SPI pin (pin 18) while the one that doesn't work shows only 0.4 volts in those 2 pins.
Any clue what might be happening there? i have tried everything but nothing seems to work....

thanks a lot for any tip.

[ESP_Sprite]

Hard to say without having the physical thing on hand, but it feels like the CHIP_EN is shorted to ground somewhere, or at the very least isn't pulled up to 3.3V. That would also result in VDD_SPI not coming up. I'd suggest looking at your reset circuit first, and perhaps try to reflow the ESP32C3 chip second.

[MRamone]

thanks Sprite,
no, it is not shorted to ground, it must be something else

[FrankSchwab]

CHIP_EN MUST be driven high by your board. If it's not high, you must figure that out first. Normally, that's a pretty simple circuit (a pull-up resistor, and probably a reset switch). If that pin is not at 3.3V, nothing is going to work.

[MRamone]

sorry guys, my bad, it is not chip_en that reads only 0.4V, it is the boot pin (pin 15) and as mentioned VDD_SPI pin (pin 18).
chip_en is not shorted to ground, i read 319 KOhm resistance between that pin and ground.
sorry for the confusion.