A while ago I bought a Grove RGB Backlight LCD from the official Seeed Store, and right away I had problems with setting up the RGB Backlight. I'm using the V5.0 LCD, with the text output working "as advertised" and strangely enough after running this I2C Diagnostic Code:
#include <Wire.h>
void setup() {
Serial.begin (115200); //***** make sure serial monitor baud matches *****
// Leonardo: wait for serial port to connect
while (!Serial)
{
}
Serial.println ();
Serial.println ("I2C scanner. Scanning ...");
byte count = 0;
Wire.begin();
for (byte i = 1; i < 120; i++)
{
Wire.beginTransmission (i);
if (Wire.endTransmission () == 0)
{
Serial.print ("Found address: ");
Serial.print (i, DEC);
Serial.print (" (0x");
Serial.print (i, HEX);
Serial.println (")");
count++;
delay (1); // maybe unneeded?
} // end of good response
} // end of for loop
Serial.println ("Done.");
Serial.print ("Found ");
Serial.print (count, DEC);
Serial.println (" device(s).");
} // end of setup
void loop() {}
from this post:
Uno + Grove Shield + Grove LCD RGB Backlight not working.
It shows both of the I2C Addresses for the LCD and it's Backlight (Which is normal):
/*
I2C scanner. Scanning ...
Found address: 48 (0x30)
Found address: 62 (0x3E)
Done.
Found 2 device(s).
*/
And the code cannot be wrong, because I'm using the Official Library for the device along with the example code snippet.
I'm really confused, and really hope that I wouldn't need to buy another one 
.
Thanks in advance for your contributions.
KronTheDev