Previously their was no radio in my car I plugged the wires of the new radio into the butts of the harness and try to start and the alarm sounds I mess around a little bit and get the car to start and radio works I go inside come out and put the radio into the slot try and start car alarm goes of have to unplug battery I unplug new stereo and try and start car and alarm sounds I did cut the ground the black wire and twisted it to the wire without the but and did the same with the yellow power wire and wraped with ductape to avoid short both wires are wrapped good and no stereo is install I try to start and alarm sounds I don‘t know what to so I‘ve made sure all Connections are good and alarm sounds with one turn of the key I‘m quite lost and had plans tonight that I can‘t do just because I tried to install a radio
Do not use the harness,wire the system this way,(Yellow constant power supply strait from Battery) (Red switchable power supply to any fuse in your fuse box that powers on or off with a turn of the key) (Black to any clean steel with a sheet metal screw) (the rest are speaker wires that should also be wired from the stereo to each speaker.You may have a few wire's to be used for power antenna and a remote turn on for external amps,make sure you tape up all wiring even the unused one's.
On my VW New Beetle, the diagnostics and alarm system are run through the oem radio. Stupid, but thats how they do it. Contact your dealer to find out which aftermarket radio is compatible with your make/model. EDIT: On my 98 bug, when the alarm goes off like that, there is a sequence to use to shut it off. Open the drivers door, then the hood, then the passenger door, then the trunk. Then go around and shut them in that same order. That will shut the alarm off.
