Do I need the dealer to program a new remote if I only have 1 ?

 

yes need two if U want to do it yourself

 

to program a new key yes you need 2 keys, with one is not possible and you have to go to the dealer

to program a remote you only need to have one remote

switch ignition on

using a programmed remote press and hold the UNLOCK for 10 seconds
after holding the remote unlock for 4 seconds press the the panic button and release together

if the vehicle horn makes a noise you are in program mode

now press any button on the new remotes, you can program 1 2 or 3 more remotes

switch the ignition off and wait 32 seconds ,horn will beep again
you are finish test your remotes

 

hey supra b4 u give out info please check what u say to be true.
The keys for the 06 300 is a key and remote in one unit not separate like older cars.
So back to what I said u will need 2 working keys to program a new one.