Arduino uno is not uploading and reset not working ??

I'm working on my arduino uno for months but not suddenly it stopped working...

The problem I am facing are:-

  1. It's LED 13 is continuously glowing and Tx and Rx LED are not working
  2. RESET is also not working, neither External button nor RESET pin
  3. I can't even upload any program in the arduino.

when I try to upload any program,the uploading hangs at the end. Driver is working fine and my laptop is detecting the arduino uno.

I've tried connecting with different power supplies in all power pins.

please suggest me what is the problem with my arduino and it's solution

I've tried connecting with different power supplies in all power pins.

? :o Kaputt? According your description it could be fried MCU. No problem to replace the MCU if UNO is a DIL socket version but first of all, try to disconnect everything (shields, wires...) from UNO. Try to use just USB connection. You have to see the port or device on comp. Also led should flick at start or RESET.

If nothing works then try to use multimeter and check voltage carefully on pins, Vin, Vcc(5V), 3V3, regulator, Vcc on ATmega, reset pin... Go throughout schematics. Are you able to do this?

I am having the same issue with the reset button not responding to being pressed.

I am trying to control a fuel injector using the timer2 with a reduced frequency output of approx 30Hz and have a simple 12V buzzer connected to the mosfet IRF5305 output to represent the injector so I can hear the frequency while modifying the pulse width.

Everything was working great last night then I went to try and measure the output signal from the drain using an Oscope and the buzzer went from a pulsing buzz to a steady state tone and then my entire laptop powered down.

I have a diode installed on the terminal block where the PWM signal is coming out of the arduino Uno and connected to the breadboard that I thought would protect this from happening but Electricity isn't my first language. Picture is attached of wiring right before I went to measure the signal coming out of the mosfet.

I think the mosfet is a IRF5305 which is a negative voltage one which took me a while to understand the function and my lack of understanding is probably how I killed the board. No smoke was released but the laptop shutting down makes me really nervous.

I was connected to the Uno via USB cable in order to monitor the pulse width via serial monitor. I am guessing that the higher voltage from the external 12V battery supply, (with a 5 amp inline fuse), somehow was fed into the DO pin9 and then into the laptop. Laptop was running on 110V AC power from standard laptop wall charger.

I know that the answer is probably in the code I haven't posted so I need to post the code and will do so in a few hours bc its not on this computer.


12 volts to an I/O pin would certainly kill an Arduino probably stone dead.

Could you edit you post a little please as the great long block of text is hard for some to read

Line spaces would help.



Thanks for the quick reply and confirming my fears.

  • First: Is there any way to revive this board?

  • Did I kill one thing in particular that can be repaired or is the whole thing toast?

  • Second: what is the best way to protect the Uno board in the future bc I don't see this being the last board I fry given my limited level of understanding.

Again thanks for the help. I am struggling to make the transition from mechanical to this electrical magic.


If the computer no longer sees it the I would say TOAST.

Given the many other components 12 volts could have fried I would say TOAST.

For future reference.

  1. Never ever move wires around when the board is powered.
  2. Double check each connection /component the same way you would when torquing bolts or assembling a mechanical object to be sure it is correct.
  3. Get and learn to use a multimeter. (does not have to be fancy)
  4. NEVER use boards near metallic or conductive surfaces.
  5. Grab some basic electrickery books from a library and spend a few minutes each day with them.
  6. NEVER let the magic smoke out again.

This books covers much of what you will need to know and get you up to speed in an easy to follow fashion.

This KIT will do the same but has the specific parts you need to complete each chapter. It will leave you with a lot of ideas for future projects too !


That symptom is consistent with hardware damage. Unfortunately the parts that die are all surfacemount parts, and multiple of them are damaged if both L-led is stuck on and it doesnt appear as usb device. Unless you have hot-air rework tools and the experience using them, it is not repairable. I do not know of any attempts to repair boards with this symptom that was successful, even by experienced people with hot air stations and experience using them. You let a high voltage (or negative voltage) get into the power rail, and burned out multiple parts.

Buy a new board and be more careful.

Thanks for the suggestions on best practices and link to the resources for improving my magician skill-set.

I inherited an blue Uno board that has both leds turn red when its powered on. I don't know the history of this unit but I would guess it is toast also?

Other posts when Googled suggest it is a clone board with a different USB converter chip. Does anyone have any advice using a CH340G converter?

Clones often use TWO distinct alternatives to the serial convertor.

CH340/341 ignore that its a chinese site this is the official driver.


CP2102 Again the official driver.

Having them installed wont harm and certainly come in useful down the line.
Unless you use the CREATE online IDE in which case they are included.


The good news is the board that was damaged from the 12v being fed into the output pin still communicates with the laptop via USB so I didn't kill everything.

Do you think there is a chance it was just the ATMEG328 chip that is toast?

I am not able to program it and get the error: avrdude: stk500_recv(): programmer is not responding avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x60

I have ordered another board and will try to be more careful. Thanks,