Rear Parking sensors wiring

[Johnyboy64]

Hi to all.
I'm having problems finding which is the reverse live on my DS4 2013.
I've had the bumper repaired, and while it was off the guy drilled/sprayed/fitted my £8 Ebay reversing sensors.
I said I'd finish the wiring off.
Easy.
No it's not.
I've got the emanuals prog installed but it won't let me look at wiring diagrams without the RPO number.
I've spent hours Googling where to find it, which is how I ended up here.
I found a post from 2010 about this. I can't find anything on my car that resembles an RPO number.
I followed a link to a site that does tell you, if you register, but it only accepts trade.
To get at the wiring block to try to identify which colour could be the one looks like major surgery.
Can anyone shed some light on this for me please?
I've attached some photos in hope.
Thank you.
John.

The colours are, from the top -

2 x mustard?
1 x red
1 x purple
1 x green/yellow
1 x grey
1 x brown

The labels are all I can find anywhere on the car.

[xantia_v6]

The rpo is usually on the tyre pressure sticker

[GiveMeABreak]

Your RPO is 13365

For the rear LH lamps on the BODY, yellow and green is the common earth for all the lamps on that cluster.
on the left hand side, Pin 2 is the reverse feed, with the earth in pin 3
on the Right Hand rear Body unit, the reverse is Pin 5 with the earth in Pin 4

[Johnyboy64]

Thank you so much for the replies.
Xantia - I've looked everywhere for stickers. There's the VIN on the door pillar and one on each headlight, Nothing anywhere that I can see. And believe me I looked yesterday in sheer desperation.

Givemeabreak - That's exactly what I needed! Thanks.
Didn't know about the VIN number. I'd seen it posted on the one I mentioned from 2010.
With that RPO number you supplied I've now been able to get into my emanual.
Thanks again.
But, now, I'm sure I'm sure, but not altogether sure which colour is the feed....
I've attached the drawing from the emanual.
I'm assuming you are counting brown, on my photo, as pin 1, grey as pin 2 and g/y as pin 3.

I'm using the left cluster so I'm hoping grey is my reverse feed.

The drawing just confuses matters. In my world at least.
Am I correct or just completely wrong?
Thank you.
John

[xantia_v6]

Pin 2 is the feed, as Marc said above and the number 2205 should be printed along the wire for identification.

[Johnyboy64]

Thanks for the reply.
I understood it was pin 2, but the drawing is configured 624513, not 123456 or 654321, which confused me.
Anyway, I had to strip the side trims etc out to get at the cables and unwrap them to find the 2205 number, which I'd have preferred not to do.
2205 is the grey wire, so it must be 123456 from the bottom up, brown being 1.
I only point this out in case anyone else gets easily confused like me.
But, I've just finished and it all works.
So my thanks again to both of you, without your help I'd still be Googling and head scratching.
Kind regards,
John