Wiring in a modern stereo...?

[macaroni]

Hi,
my Murena has an old Panasonic stereo and I want to use my more modern Sony.
The Panasonic seems happy to work with just the red-live and black-earth wires present. The Sony appears to need another 2, a blue and a yellow wire. What are these extra wires for and from where can they be sourced in a Murena?

Cheers,

Antony 

[Lennart Sorth]

not sure, but I would guess they could be control-wires, so that mobile phones ot similar can mute the radio ?

As I recall, my previous radio had a "mute" wire, which when given a 12V pulse, caused the radio to search for the next available station. I have seen that operated by the unused play
in the indicator stalk, when you pull it slightly towards the steering wheel :-) 

Sadly I cannot remember anything about my curent Sony MD thing - but I will have to redo the complete wiring, as it was done rather poorly by some jerk long time ago.  ( = me )

/Lennart