20x4 LCD display suddenly stopped working. Burned my Ardruino?

Hello everyone!

Can you please help me with an issue that I have recently?

I used a 20x4 LCD display with i2c on a Arduino Uno and programmed the code for it.
It worked like a charm, for a couple of hours and after powering it off and on a couple of times the display wound display the text and numbers anymore.

This is what I did to figure out what the problem is:

*New display and new i2c
*re-programmed the code and upload the same code to the Arduino.
*New cables (shorter )
*Solderd the cables directly to the i2c and the the pins that will fit in the Ardruino.

Nothing worked out.

Solution: New Arduino Uno

Same story: Worked for a couple of times and after 30 minutes it stopped working after swithing it all off and on.



*New display and new i2c
*re-programmed the code and upload the same code to the Arduino.
*New cables (shorter )
*Solderd the cables directly to the i2c and the the pins that will fit in the Ardruino.

This really freaks me out, there is no short circuit I know for sure.
Is it possible that my wires are too long?
I used about 1 meter of cable, can the resistance couse the Arduino to fail?

Fact: the code works and I am sure that a other Arduino will fix the problem again ( for a couple of minutes but I need something that will work for a long period.

Any thoughts?


Solution: New Arduino Uno

Does the old one still work with example sketches such as Blink ?

What does your program do ? What pins does it use and what for ? What, if anything, is it connected to apart from the LCD ? Post it here for comment.

Run this with the LCD connected and post the results here

// --------------------------------------
// i2c_scanner
// Version 1
//    This program (or code that looks like it)
//    can be found in many places.
//    For example on the Arduino.cc forum.
//    The original author is not know.
// Version 2, Juni 2012, Using Arduino 1.0.1
//     Adapted to be as simple as possible by Arduino.cc user Krodal
// Version 3, Feb 26  2013
//    V3 by louarnold
// Version 4, March 3, 2013, Using Arduino 1.0.3
//    by Arduino.cc user Krodal.
//    Changes by louarnold removed.
//    Scanning addresses changed from 0...127 to 1...119,
//    according to the i2c scanner by Nick Gammon
//    http://www.gammon.com.au/forum/?id=10896
// Version 5, March 28, 2013
//    As version 4, but address scans now to 127.
//    A sensor seems to use address 120.
// This sketch tests the standard 7-bit addresses
// Devices with higher bit address might not be seen properly.

#include <Wire.h>

void setup()

  Serial.println("\nI2C Scanner");

void loop()
  byte error, address;
  int nDevices;


  nDevices = 0;
  for(address = 1; address < 127; address++ ) 
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    error = Wire.endTransmission();

    if (error == 0)
      Serial.print("I2C device found at address 0x");
      if (address<16) 
      Serial.println("  !");

    else if (error==4) 
      Serial.print("Unknow error at address 0x");
      if (address<16) 
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");

  delay(5000);           // wait 5 seconds for next scan

Have you calculated powered consumed by 20x4 LCD display

How you powering the 20X4 LCD display. R u using Arduino power or external power source??

please make ensure the brightness section working properly. check if you give input you can vary brightness properly

First, thank you very, very much for the reply!

I am speechless, came home today ( did send the question during work ) and give it a try again.
On the second arduino, first display and original wires, worked.
Off/on, 30 times… removing cables and did a reflash the code… still working :astonished:

First Arduino is shipped back, that one didn’t work for sure :zipper_mouth_face:
Long story short: it works and I can’t get it to fail again.
I have bad karma, please remove the post.

Thanks, many thanks for the help and the suggestions.