What is this wire for???

Car= 1998 Pontiac Grand prix se.

I was installing new speakers in the doors and in the rear deck and an amp to power them. i decided to use a LOC since I was going to use the factory HU. When i took out the HU i noticed a red wire coming out of the HU near the antenna plug in. the wire wasn't connected to anything it was just in there. the end was stripped and it looks like it might have been spliced to another wire at some time. Does anyone know what this wire is. I'm thinking it might be a ground or something to do with the antenna. I taped up the wire for now and put the HU back in

The wire is seperate from the wire harness and goes directly into the HU.:confused:

its probably the rem wire for an accesory such as an amp.

get a multimeter, check voltage on it and on a known ground with the headunit both on and off.

Does the HU come back on?

if the muiltymeter reads about 7-8 its a remote just in case you did not no

I figured out what the wire is for it is a remote wire.