I have two antenna cables routed trough to the area around my CD head unit. One is a large black and red cable with a smaller red power cable and a black ( i presume earth) cable attached. The other antenna is a single grey cable. Which one is the original - i.e. for the antenna in the back screen. I have another antenna on the car (installed by the previous owner) which I had assumed was for the car kit he installed ... however now I'm not so sure!

post pictures

personaly i'd go with the oe one

As Craig says please post pics.

I would think that the previous owner has fitted an aftermarket aerial due to the Coupes one not being all that good. If it has power connections I would imagine its maybe a glass mount one.

I'd love to post pics, but I've just installed a new head unit and the wiring is dodgy as hell back there - so I daren't take it out as long as it's still working! I'm using the large red/black cable which has a small red and a small black cable in the same sheath which splits out at the end! The other available cable is plain grey - which I think is the OE antenna? It would be nice if someone could confirm this without pics!

Plain grey is the OE aerial.

If you are using the other one it will require power to get the best reception from it.

Thanks Matty. I connected the power - getting decent MW reception now. It's good to know that I'm using the antenna drilled into the back of my car and it's not just for a crappy 90s Nokia phone

you installed a head unit?

did you cut the wires?