Just installed a Parrot handsfree 3200ls that i got given. It's all in and working but as i was doing it i had a problem/ queery.

When i was puching the HU (CD70) back into place the display was changing to 'External In'. What is this mode? When i use the 'Aux in' it displays just that and i wasn't aware that the ls3200 had any sort of additional input. There was a pink wire with a spade on the end of it attached to the iso lead that i bought when i taped up the end of it so it didn't ground on the chassis the problem was solved. Any ideas?