Annoying Beeps when Starting Truck

The truck is a 2005 TRD OR DC. It makes five annoying beeps every time I start the truck. It starts the beeping as soon as I turn the key to start. Is this a standard system check sound or something else?

 

belt minder, probably.

 

X2

Seat belt chime

 

^ this

Try buckling your belt before inserting the key, see if this makes a difference.

I get endless beeping every time the key is in (regardless of position) and the driver's door is open. Passenger door doesn't beep with the key in. ??? TOYOTA

 

Thanks, you were right. I thought the belt reminder was disabled because I can leave my seatbelt off while driving and it doesn't make any other sounds other than at startup. Looks like it's time to disable it.