New here
need help ,hope someone can please

have a f150 supercab 4x4 , 5.4, bought secondhand
has a remote start i think is aftermarket,can't find any brand name or # on it.
just a black box,the key fob has "Premier"marked on it.
The problem is that since i had the truck ,the only way to start the truck is to press the unlock button on the key fob.Had a new motor installed and the dealer said hey found that problem but wouldn't say what.after that you could start it as normal with the key.had to change the truck battery and it went back to having to use the unlock button on the fob. Now iam having a problem with the fob,can't get the truck to start at all unless i pull the battery out of the fob and back in again and then press the unlock button on the fob.
Would like to find out how to get it back to be able to use the ingition key to start the truck as normal.
aprreciate any help with this

 

Can the dealer remove the black box?

Take it to an installer and have them install a new alarm/remote start?