Can't get I2C Module to work with LCD

Hi guys, im trying to display text in my lcd with the i2c module but somehow when i increase the contrast all i can see is white boxes only in the first line.

i've used the hd44780 diagnostic example to debug this problem and this is my output:

********************************************************************
Serial Initialized
--------------------------------------------------------------------
I2CexpDiag - i2c LCD i/o expander backpack diagnostic tool
--------------------------------------------------------------------
hd44780 lib version: 1.3.2
--------------------------------------------------------------------
Reported Arduino Revision: 1.6.7
CPU ARCH: AVR - F_CPU: 16000000
--------------------------------------------------------------------
SDA digital pin: 18 A4
SCL digital pin: 19 A5
--------------------------------------------------------------------
Checking for required external I2C pull-up on SDA - YES
Checking for required external I2C pull-up on SCL - YES
Checking for I2C pins shorted together - Not Shorted
--------------------------------------------------------------------
Scanning i2c bus for devices..
 i2c device found at address 0x27
Total I2C devices found: 1
--------------------------------------------------------------------
Scanning i2c bus for all lcd displays (4 max)
 LCD at address: 0x27 | config: P01245673H | R/W control: Yes
Total LCD devices found: 1
--------------------------------------------------------------------
LCD Display Memory Test
Display: 0
 LCD stuck BUSY status
--------------------------------------------------------------------
No working LCD devices

As you can see, the LCD shows an BUSY status, i've searched for solutions in arduino's forum, but i still cant manage to solve this.

Im sending the soldering and the connections:

Images



Those solder joints do not very good. I suspect that that may be a problem. Maybe purchase an LCD with the backpack soldered on from the supplier. And work on improving your soldering technique.

Lead/tin solder is easier to use than the lead free stuff. For hobby use it is fine. Use it in a ventilated area and limit contact with skin. I have been using leaded solder for 60 years and am fine (arguably :slight_smile: ).

Sparkfun soldering tutorial.
Adafruit soldering tutorial.

Hello, @shadowoff09,

Put a lot of flux on your LCD pins' solder, then re-heat just until flowing. The result should be shiny with a slight curve (not dull blobs). If you have solder wick, remove some of the blob.

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