Analog Read Problem

Hello

Sorry if this has already been posted, I did a search and couldn’t find any answers.

I have been (successfully) using the analogRead function to read in a signal from a sensor. The sensor outputs an analog DC signal, from 0-5V. This resulted in analog read values of 0-1023.

However, when doing some tests today, the value being read in is a constant 600.00.
I assumed this was an error from the sensor, so i disconnected everything from my arduino board – still 600.00.
it’s as if board’s input is being overridden by some constant.

any ideas?
thanks in advance!

edit: forgot to mention, i havent changed the code since it was working last.

changing the read in pin from 1 to 2 fixed everything.

not a clue why though...