Grey cable in the spare wheel well

[Sidewinder76]

Hi all,

I found a grey cable with a purple plug in the spare wheel well yesterday that isn't connected to anything.

Does anyone know what it is?

Thanks in advance.

[PaulP38a]

doesn't sound like anything that is there as stock. Got a photo?

[RR P38]

Does it lead off to the right hand tail light assembly or the left side?