Wire spliced into rear light?? C5 tourer

[WickedElf82]

Hi the brake/indicator lights stopped working on passenger side cluster on my Citroen c5 tourer and I thought it was maybe just the bulbs but on closer inspection there is a wire from another part of harness that has been spliced into the connection block? Anyone any idea what’s happening here? I assume it’s to bypass the ground wire or something possibly, any help is greatly appreciated.

[Ross_K]

All that insulating tape...looks like some quality workmanship I don't you could make any judgement about its function based on a photo

Towbar wiring is the first thing that springs to mind in that area?

[WickedElf82]

Yes the other harness is very baffling and I don’t have a tow bar on the car either so dunno what’s going here especially as you say the way it’s been taped up with a single wire going into my brake light connector block which was soldered and taped aswell

[Ross_K]

The wiring on the left looks very suspect as well - I think you'll need to get a multimeter, unwrap all that insulating tape, and trace where those black wires are going.

Unfortunately it's impossible to guess what was going on in the brain of whoever did it... Ex-taxi or ex-police maybe?

[myglaren]

Had it been one side and to the reversing lights I would suspect a dashcam with a rear-facing camera.
Would hardly be needed to wire to both sides.

[WickedElf82]

Yeah unsure what it’s all for tbh, there’s a black box attached to that harness, there’s also another connection block above a black cage that I’d assume was for a cd changer or something maybe too

[Jay-Bruce]

I'm going to guess that this is wiring for the electrics for a towbar's electrical connector?

[Ross_K]

Yeah unsure what it’s all for tbh, there’s a black box attached to that harness

Any part number or identifying marks on the box? Three different kinds of cable going into it doesn't inspire confidence .

[WickedElf82]

There’s no tow bar connected at all unless one was removed by previous owner at some point but was never one sold with the car etc

[WickedElf82]

This is on the back

[WickedElf82]

Inside of box

[Ross_K]

That's wild. I can't find any info about it online.

If I had to guess I'd say it's some kind of multimedia controller (maybe cameras) or a strobe light controller?

I'm stumped (although that's not hard )

Time to start tracing the cables...

[WickedElf82]

Yeah it is just strange as I can find anything online, doesn’t solve my issue of brake/indicator light on passenger side lol, there seems to be a wee orange volume screw on the box too so unsure exactly what it is controlling tbh

[Hell Razor5543]

Reversing sensors? The screw could be either sensor sensitivity or beep volume.

[WickedElf82]

Yeah I was thinking that tbh but I’d need to trace all the cables to see where they lead too