I have tried this twice on renaults and worked both times for me, take care when fitting and make sure power is switched off to the stereo if you follow the steps you should not have to disconnect the radio any damage is at your risk.....(sorry dont want to be sued!!) Plus ensure you can select AUX as a source, if not press and hold button that looks like a musical note until it beeps at you to get into expert mode, scroll thru to AUX and select on.
First off have a look at this site and get yourself the blaupunkt aux adaptor lead, i went for the jack plug style as it plugs into your head phone socket and has 1.9metre lead, the rca type has only 30cm
https://www.bluespot.co.uk/stock/auxin.asp
once it arrives you will need a pair of radio DIN ISO radio removal tool, a hacksaw a small pair of wire cutters (side cutter) or small file and a couple of small tie wraps, dont panic this is to cut up the connector not the car. I dont have a picture of the connector pre mod but the pictures below will give you an idea of how to cut it up. There is basically three pins wired up next to a clip assy, the clip needs to be removed and a small groove put in its place to avoid damage to a pin that will be external to the connector, then you need to remove the connector body that is not wired up, I cut it through the centre of middle pin and then trimmed it up with the wire cutters, take care not to shatter the body.
Once the cuts are made and small groove in place remove your head unit, Tip put your gearstick in 3rd gear and put a thick sock over it, this will act as a support for the radio without scratching the knob (im trying to keep a straight face here). the two pictures below show where your new connector goes, looking at the rear on the right you will see a yellow mini iso this is your remote control and display data. the two connectors onthe left are the power and speaker connectors. there are two connectors not in, towards the front i believe is the multichanger or tunepoint connector, the final blank space is between the yellow connector and the large power connector, you put your new connector here the picture shows my connector already in place, closest to the power connector with what was the clip towards the yellow connector leaving a row of pins unconnected between them.
Take care when pushing in place if the middle pin on the outside is bending make the groove bigger and retry, once happy, use a couple of small tie wraps (zip ties) to anchor the lead to the aerial lead to prevent it being tugged.
Now you just have to decide where you want the lead to go, for now i simply dropped it out the back of the radio hole to the left down the side of the passenger area where i managed to pull it out at the base, then fed it into the area behind the flap covering the ECU interogation socket. From there i was able to pull it so it comes out under the cup holder ciggie lighter, I use this area to hide the mp3 player when parked, when driving i simply place it in front of the cup holders see picture. Obviously where you put it is upto you, when i had this setup in a laguna i had it in the glovebox however this time have gone for a minimum drilling holes stratagy
When refitting the radio i found it sometimes sat at an angle the bottom not sitting correctly, if you keep the removal tools in and apply a small amount of pressure down on them to get the radio to the same angle as the facia as you push the radio in you may find it will seat itself correctly, if it wont go in fully pull it back out and check that your wiring is not fouling the centre locating spigot (grey plastic thingy at the rear)
and thats it, its cheap cheerful and limited to the power of your mp3 player but if your happy just to have some sounds with minimum of fuss give it a go. Good luck let me know how it goes, unless you break it.

Bumpy and full of coconuts.
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