How do i know if my LCD Module is cracked?


I'm pretty new to electronics, recently bought a arduino 2009 and some components to mess around with. Among these is a LCD-Module, which i tried to connect to my arduino. after i while i remarked that gnd and v5 are not like in most cases gnd on pin 1 und v5 on pin 2, but reversed. after changing that and finally managing to connect the contrast, i got: top line is completly black and the second one doesn't display anything (is blank). So, i proceded by connecting the LCD to the arduino in the way suggested in the LiquidCrystal Tutorial on the Arduino site, but i didn't get something different from the state i described.

So my question is, is this a normal state (one line black and the other one blank thing) or is this the last flickering light of life which i mostly blew of this thing by connecting it the first time (in the correct manner, NOT)?

Thx for your answers and have a nice day Michael

Link to the Datasheet: (coudn't post i in the first post)

The line of black boxes on the top line with a blank second line is USUALLY an indication that the LCD is working fine.

It's just that the contrast is not properly adjusted.

Ok, thx but when i change the contrast (via poti), only the top line changes the blackness, the bottom line does nothing, which is anyhow logic when there's nothing to display down there. why is it a matter of the contrast then?

I don’t know if i did something wrong in wiring, which seems to be #1 problem in such things. Here’s a pic of my wiring:

the only difference from the standard wiring is the reversed pinout of gnd and 5v power. the orange wire on pin 3 (on the lcd board) goes to the gnd → contrast.
the two empty slots on the lcd module are dead, i only had 2 of those black contact things with 8 slots, so i soldered them, leaving 2 pins empty.

this whole thing should be alright with this code from

I don’t get what i’m doing wrong, so if anyone does… =)