LCD not displaying character

Pls fellas I bought a 16x2 LCD and am using Arduino Uno R3 SMD but whenever I finish wiring I don’t see any character it always goes blank leaving the contrast even when I adjust the potentiometer and the contrast becomes mild it still ain’t showing a thing I used the example on the ide which is blinking LCD don’t know yet if it’s from the Arduino Uno or the jumper cables pls any suggestions am on project which would be submitted to the sch asaptmp-cam-637151462484349435

Can you say which LCD library you are using and also post the code example which you have tried ?

This guide looks quite good:

Please check the solderings at the LCD.

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

#include <SoftwareSerial.h>
SoftwareSerial SIM900(7, 8); // gsm module connected here
String textForSMS;

int pir = 10;// pir sensor is connected with pin2 of the arduino
int touch= 9;
int ledpin = 13; // Alarm/light can be connected with this led
int buzzer= 6;

void setup() {


SIM900.begin(9600); // original 19200. while enter 9600 for sim900A
Serial.println(" logging time completed!");
pinMode(pir, INPUT);
pinMode(ledpin, OUTPUT);
digitalWrite(ledpin, LOW);
pinMode(touch, INPUT);
pinMode(buzzer, OUTPUT);
digitalWrite(buzzer, HIGH);
digitalWrite(ledpin, HIGH);
digitalWrite(buzzer, LOW);
digitalWrite(ledpin, LOW);
lcd.print(“Please wait !”);
lcd.print(“welcome to intruder alarm sys”);
Serial.println(“please wait”);
Serial.println(“welcome to intruder alarm sys”);
delay(5000); // wait for 5 seconds
} @6v6gt

I changed the soldering to a male header and slot it in breadboard as seen belowtmp-cam-3479242667093372123@paulpaulson

Since your problem is with the LCD, I suggest you find a much simpler example which handles only the LCD and simply prints a test message on it. Your code includes a SIM900 interface.

You must also check that this statement corresponds with the pin numbers you have used to connect the LCD to the

Uno: LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

Can you post a better image please, if you look at it, the resolution is very poor.

Thanks… Tom… :grinning: :+1: :coffee: :australia:

Ouk I tried that too especially that with blinking “hello world” and it seem same too the connection and soldering are ok it worked some weeks back and then it stopped I have also changed the LCD the third time and all seems same am thinking is from the Arduino Uno don’t but u may since u are way here before I.
The thing is all other components attached are still working fine led, touch, buzzer, PIR except for the LCD alone

OK. Post this code as well.

here is a better resolution @TomGeorge

Ok Sir

STOP calling people fellas & sir - I, for one are neither a fella, or a sir.

Please describe in detail your connections, or draw a schematic, as these photos are usless to work out what is connected where.

Your use of stranded wire in a breadboard is not helping you. If you don’t have access to proper breadboard jumpers I suggest you cut and strip to expose fresh wire. Twist the copper strands together. You want the resulting “pin” to be narrow so, if necessary, exclude some strands from your twisted bit and cut them off. Use your soldering iron to carefully apply solder to the twisted to form a solid “pin” that you can then insert into the breadboard and Arduino pin sockets.

Or just order up some proper jumpers. Something like these.

You may still have other problems but that messy nest of wires is sus.

Ok I’ll right away

Hey guys it’s now not a problem I checked my uno it had a partial solder which I fixed and repaired my layouts as suggested by you guys and it was a wao cuz it later gave me what I needed. Am grateful to you all :pray::heavy_heart_exclamation: :heart: and am loyal @Blackfin @TomGeorge @6v6gt @missdrew @paulpaulson u guys made it for me God bless you all it’s kul in this forum with u guys

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