warning lights

While driving on saturday the warnining light for ( Control system for exhaust came on ) then after a couple of hours the ( DPF ) warning light came on got home rang Skoda assist who said they could not get to where i live as roads were too bad but as it had not gone into limp mode would probably be okay to use as i had to go to work sunday,on my way home sunday night dpf light went out not from giving it a blast as roads too bad,went to work Monday and the other light went out,rang Skoda dealer who reckons the fault has cleared itself and as long as lights dont come back on it will be okay but could give no reason for them to come on in first place.Anyone any thoughts what could cause this ?