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So I'm sure these threades have been done over and over so my apologies. But I took my car to a local stereo shop and had my system installed. Normally I do my own but honestly getting lazy as I get older. Anyways, they screwed everything up and has never worked right. So I've been slowly fixing everything myself. First and foremost there has been a buzzing and crackle in the speakers since left shop. I rerun the amp wires and speaker wire to make sure no interference. Then I switched the front speakers to make sure they didn't blow them. So I pulled the head unit and they even though I bought the proper harness and they had jumped the the switch power to the vent wires and had the remote wire tied with switch power. I re installed everything the correct way the way it suppose to be, but not getting CAN signal from reader to turn on switch power wire. I spoke to Axxis harness tech support, they said alot don't wait for the car to sleep first before disconnect factory radio which throws a error to CAN and there module is read only so will not reset error. They said easiest is plug up factory and reset error and then correctly let sleep the plug in new stereo. Problem is I don't have factory anymore, and I don't want to unhook battery if I absolutely don't have to, because of issues after I read. So is there a way to clear CAN command without radio or what's the proper fuses and will that soft reset clear the errors?

Also I've been surfing threads looking for answers and seen alot that said they were having a issue were there aftermarket stereo don't keep memory, read that yellow wire from harness doesn't actually stay powered all the time and causes stations to be wiped. So if this is true with besides they screwed up mine I've witnessed this myself, should I run my own independent power wire for my stereo?