If the decimal point in the retard display is blinking, you're in open loop. When it's solid, that's closed loop. (or you could install the powerlogger and it'll tell you when you're in closed loop
) That's per the instructions. I've never payed attention to see if it works like that after installing the powerlogger scanmaster chip.
some chips like the turbotweak run open loop at idle but I don't know if it reports it to the scanmaster either.
http://www.fullthrottletech.com/attachment.php?attachmentid=172&d=1135610103