check the 4 timer pins on the timer, but just fix it and check on it when the lights go on and off every hour or two,your good thow it will take the plants a couple of days to notice once the lighting schedule is changed so 8hours wouldnt heart.my hps lights turned off when they were suposed to, but the flouro light that lights up the room which is uaully kep off at all times was left on for an extra 8 hours during their dark peroid, what should i do????? help!!!