what's this wire?

[03MSPRO]

there is a yellow wire that comes from under the carpet and goes thru the firewall and to the battery cable with a 15A fuse. What is this wire for?

[pdhaudio83]

amp power.

[pdhaudio83]

sound system. it goes on the driver side and to the back under the plastic things to the trunk.

[03MSPRO]

thanks. that's what I though it was for. I saw for the 1st time yesterday when lloking for the green wire to hook up the boost gauge.