Car radio and alarm not working
Radio and alarm not working...i change the
battery and the alternator....start up
everything but the radio and alarm not
I assume you have checked the fuses for these items? If you have access to a volt meter you could check to see if you have power to the back of the radio at the wiring harness
You may have corrupted the programming in the BCM by disconnecting the battery without installing a saver tool, unfortunately the only place to get it reflashed is the dealer.