I have the stock keyless entry and alarm on my 98 LT Blazer.
Is there a way to get the turn signal, or any other outside lighting to flash when I lock or unlock the doors with the remote ?

 

On the 98+ ones, the lights should flash. Press the unlock button once to unlock the drivers door and the taillights and parking lights should flash once, press it again within a few seconds to unlock the rest of the doors and they should flash again. If you lock it with the fob, press it twice and the horn will chirp. If your keyless entry works, I don't know why the lights wouldn't.

 

Both fobs work fine, also the horn chirps when the alarm is engaged via the fob, but no light signal. Is there a way to reprogramm the BCM ?