1994 gmc sierrea after market stereo replacement

SOURCE: what wire do I connect my after market stereo

You need to get the Wire color code for your pacific stereo and for your pacific car. Your really lucky if they randomly end up to have the same color code. Each speaker has two wires that need to be connected to the car, a negative and a positive. All negative wires SHOULD be connected to only other negative corresponding wires. Not a huge deal but you sacrifice sound quality. There is a "12v + Constant", one on the stereo and one on the car that need to be connected. There is also a "12 Switch" on each end that need to be connected. The constant is continiously running power to your radio to keep the time accurate as well as keep your setting on your stereo. Some have what is called a memory wire, only one, either coming from the car or the stereo that needs to be connected to the constant connection. You also have a thicker gauage wire that is usually black on both ends, but you never know, that needs to be connected. Electricity cannot travel through thin air, it has to be physicially in contact with the ground(indirectly or directly). If your hooking up a sub or an amp I really haven't gone through the proccess, but for a simple 4 speaker and stereo system, that should be all that you need, for more cars. All Different. Some have two costant wires. DO NOT use both to only hook up stereo. You use only one with one appliance the other is for amps, and subs. If you have both of the constants from the car connected to the constant on the stereo your car will not start, and your gauages will short out until one of them is disconnected. If you are only use one, it is a good idea to use the larger gauage wire. The smaller the wire the more risk of fire(in correspondance to the watt to gauage ratio). I hope this helps. Spent all day doing it. Never found a guide. My advice is to call the manufactuers personally because none of the info I found matched up to the other sources I found.