I have 03 F150 with about 260,000 km. Truck appears to be running well but I am getting an unusual chime (never heard before) after start up. The chime will be 5 sets of 5 chimes after ignition. It then stops and will not be heard again until the next start up. There are no warning lights and all fluid levels and gas cap appear OK.
This chime is not like the seat belt warning, door ajar warning or any other I may have heard before.
Any ideas or comments?