Hi, sorry for the delay....I've had a look at mine and apart from the black wire mines a different colour...I've had a look on the schematic on here and there isn't a yellow ...it's brown, black, red...but give the location of your wires I would very much think that's what they are for...it's the only logical explication. Have you tested them to see if they are live....my radio wire is live all the time, but it doesn't necessarily mean mines right and yours is wrong....I would have thought that the plug would be for the cigarette lighter.....