16x2 LCD backlight

I have one of the 16x2 LCD and for me to get any brightness out of the backlight I had to jump the resistors on the back, at 5V through the resistors was so dim it was barely noticeable, now after jumping them it looks normal. Just wanted to post this incase the data sheet is off, I can’t believe I’m over-driving them at all. I ran them for about 12 hours straight and there was no heat output and no failure.