hold the trip button down for 5 seconds then switch the ignition on, don't need to fire up the engine. keep holding the trip button until the service light goes off.
if like me you bought one that hadn't been serviced in years you may have to do that 2 or 3 times
I had the in02 code so I had to reset once to get rid of that then again to get rid of in01 then a third time to get rid of the oil service code....