I pulled out my pioneer deck and put it back in a now it doesnt work. does anyone know if it might be an anti-theft thing and i have to press some bottons? help, ive gone without music for too long.

 

check to make sure you did not blow any fuses when you installed it. Look underneth the hood to check the back up fuse. Then make sure u did not blow any in the dash. If thats okay check the one on the radio. From there get a dvm-meter to check your power from the battery wire on the harness, then check for the acc wire. Also make sure the ground is present.