Adding an Aux device to a Sony WX-C570R Car stereo head unit.

Many Sony stereos have this feature, look at the back of the unit.

I have a Toyota MR2 Mk3 2002. I wanted to play tunes from my phone.

This is what you need.

1 x Phono to male mini speaker jack cable.
1 x Uni-Link Adapter.

Fit the phono cable to the back of the stereo, I managed this with out removing the unit. Drivers side, UK car.
Fit the Uni-Link Cable to the back of the head unit Passenger side. (the one I purchased fitted with leg going upwards.

Phono cable cheap
Unil-Link cable / adapter 9.99 on ebay

Fit your phone or iPod to the headphone jack.
Eject the CD.
Play a track on the phone / iPod
Press the CD until the device is selected.