This is a demonstration of what the radio does, and it shows which chip where, needs to be removed in order for the radio to work with out taking it to the dealership and paying them $50 to $100 to unlock the radio for you. This saves you their excuses, and saves you money to get tunes back in your car. Side Effects to Consider before doing this: 1. AM/FM/CD Only Decks will always have the Tape icon on. 2. All Units will display CAL ERR upon first power up (goes away in 3 seconds). 3. When powered on a bench out of car, the display will dim it self slightly (BCM tells them to dim or not. Defaults to Dim without BCM signal) 4. I believe this is a wiring issue in the harness, but I have heard they can lose their Presets each time power is removed. 5. The very very later units, 2005 to the end of this style radio, need a digital "On" Signal from the vehicles BCM, so if you wish to use it on a bench, the older ones don't need a digital signal to power on. It will see that signal in car and still power on. **This system DOES NOT WORK** On radios above 2006. Later GM radios use an 11Bit, or 29Bit Data BUS (CAN, or GMLAN). All these radios need a digital ON Signal to work. There is an Adapter to send them the "On" signal for sale around ebay. This strange system has also prevented car stereo "benchers" like me from operating the units out of the car. That system defeated, it opened a whole new range of car stereos for us. Remember, if you own the car, you own anything in it. As such, you own the radio installed in the dash board, and there is no reason for the manufacturer to tell you, you can't change your radio, or install a better one, or anything with out paying them a fee. And really, ask your self "Who would steal a factory radio?". I stay factory in my own car because if curious eyes peek in and see a factory deck in the dash, they'll ignore it and move on to the next car! Disclaimer: If you screw your radio up, that's not my fault. I hold no liability what-so-ever. This is a do at your own risk modification. If you do this and do it incorrectly, and turn your radio in to a paper weight, I am not liable in any way, shape, or form for your mistake. If you are uncomfortable doing this, then take the radio to a dealer and have them do it the correct way. I had nothing to lose. These won't work in my Saturn, I bought these to add to my vast GM Stereo Collection, and to aid in figuring out the security in these, and how they were built. I purchased my units from vehicles that are now gone, crushed, and sent to be melted down. They served their life, and now their parts, these radios included, are all that remain. I purchased them aid on a form site I am a member of in getting these radios to play nice. I have receipts to verify where I purchased my units.