So, I've been trying to make an Lcd display shield I got from ebay to work with arduino. Using this very simple code:

#include <LiquidCrystal.h>

#define RSPin 8
#define EnablePin 9
#define DS4 4
#define DS5 5
#define DS6 6
#define DS7 7

#define LCDColumns 16
#define LCDRows 2

LiquidCrystal lcd(RSPin, EnablePin,DS4,DS5,DS6,DS7);

void setup()
  lcd.begin(LCDColumns, LCDRows); //Configure the LCD
  lcd.print("Hello, World!");

void loop()


Actually I've tried several simple examples, checked pins physically to make sure I'm using the right order, But no luck. backlight is on, no characters at all. Am I missing something? Or should just contact the seller to send another shield.

  • 1
    My guess: wrong contrast settings (on blue potentiometer)
    – KIIV
    Commented Dec 2, 2016 at 11:57
  • I've tried rotate it, doesnt seems to do anything
    – shdow
    Commented Dec 2, 2016 at 12:10

1 Answer 1


So, after some close inspection I noticed that the blue potentiometer wasnt soldered in correctly. Also, its needs to be turned quiet a lot to have some effect. Might replace it completely. But now it works!

  • Usually, PCB based potentiometers require many turns (~25) to cover the full range. If a pot has been used a lot, a poor soldering joint will indeed come loose. A super poor soldering joint comes loose without any help from the pot.
    – K7PEH
    Commented Apr 24, 2018 at 18:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.