If I owned a 2003 car which was still under warranty, I would want the
service records to show that all scheduled services had been carried out by
a franchised dealer - in order to comply with the warranty terms and
maintain the highest possible second-hand value.
If a franchised dealer does the service, he will turn off the light.
If the light has come on when it shouldn't have done so, this is a warranty
issue - and a dealer should turn it off for you for free.