wiring up new radios

[m1b0c]

Hello,

I noticed there are 4 speakers in m59 - 2 of which are located up front while the other 2 are in the back. I'm upgrading my Berlingo from the manufacturer's radio to a new unit. The problem is that on the back of the new stereo there are 4 RCA sockets and there are missing PINs in one of the main sockets. I assume those extra PINs on the default radio are meant for the backside speakers. Has anyone dealt with a similar problem before? Am I wrong in my assumption regarding extra / missign PINs?
Front speakers (only) do work without any rewiring whatsoever on the side of the original Berlingo harness as I've checked.

Top / back: new stereo (missing PINs top-left)
Bottom / top: original stereo

[Gryffindor]

Firstly, DO NOT just swap the radio for an aftermarket one. The original PSA radio is not just a radio, it is part of your car's comms network and without it you WILL lose control of your central display and MAY get far worse, in the form of lights, indicators, wipers, etc. not working when they should or working when they shouldn't.

There is a way to swap the radio out by using special aftermarket looms. Search this forum for details.