can display only 1 line on 16x2 lcd

I have a clone of one of the sainsmart lcds with pushbuttons.
I can’t make the 2nd line display
here is the code

#include <LiquidCrystal.h>

LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

void setup()
{
lcd.begin(16,0);
lcd.clear();
lcd.setCursor(0,0);
lcd.print(“firstRow”);
lcd.setCursor(0,1);
lcd.print(“this_is_2nd_row”);
}

void loop (){}

when I run that code the words “this_is_2nd_row” appears on the first row nothing on 2nd row.
I get same results if I run lcd begin (16,1)
if I put lcd begin(16,2) I get a totally blank screen.

I must be missing something totally obvious.

Is it necessary to power down and totally reset the hardware between downloads, is there leftover data in the lcd controller somehow? Could it be a wiring problem?

  lcd.begin(16,0);

Shouldn't that be (16, 2)?

... if I put lcd begin(16,2) I get a totally blank screen.

Try readjusting your contrast.

Don

floresta:
Try readjusting your contrast.

That is a novel thought, that helped, it was there but I couldnt see it.

correct lcd(16,2)

thanks all.