can be several things. if we have a car that notes low oil pressure ? it may have seen oil change as low oil and flagged it up. these cars need light (service warning lamp) reset.
if its a no auto oil level type? then we may have had low oil pressure to start with while system cranks up pressure from oil change e.g. new filter. empty pickup pipe etc.
it ought to go off when oil pressure is reached!
if still occurring? are we sure oil level is correct? did we use correct oil?
unlikely oil pump would stop working.. after a simple oil change but pressure relief valve might .
have a garage check oil pressure and sensor connections etc.
C'mon now WHAT kind of car, YEAR< make, model size, country of ORIGIN mileage, and MORE info like TRANS TYPE and does it have ABS! GET REAL PLEASE! IF there is NO OIL then there is NO PRESSURE! Use ONLY SYNTHETIC OIL if you LIKe your car and want to save expensive engine parts from sludging up and FAILING SOONEST!
did you check your oil level?
it will go on just after you change it then go off
