I have fitted the connects2 ipod mechanism but the HU has lost all power.

The connects2 has power, as does the cd changer if plug that in. We have tested all the wires with a different HU and they work which tells me there is a problem with the actual HU.

Anyone know what the problem maybe?

If dead what cost am I looking at for a new HU? (Symphony)

Just an idea - does that headunit have a integral fuse adjacent to the connector?

Yes it does. I'd look there first!

Then I'd make sure the ISO are fully pushed home.

A brand new Symphony is £400 from the dealers.

Thanks guys - the ribbon behind the face had come loose - unfortunately - when correcting my mate further knackered the power/volume button. He has now corrected this issue but it meant going right down to the mother board!