Review on Enhanced GM Vehicle LC-GMRC-01 Data Bus Interface by Metra by Brandon Vox

My used GM car came with an aftermarket radio that was hard wired with the radio plug removed on the side of the car. The car was originally set to play beeps through the radio and turn the radio on and off over the car's LAN. As a result there were no beeps and the ignition connector on the radio was connected to the battery (always hot). Using the VOM, the wire labels on this unit, and the car's wiring diagrams, I was able to make the necessary connections to restore the beeps and turn on the radio when the ignition was turned on and restore the delayed shutdown feature.