My speedo is jumping so I'm going to replace it but my current cable has this. The wires go connect to 2 others(cant see where they come from) and goes to the plug that Isbt connected to anything in the second pic. The car is a police spec(not sure if it ever was a police car though) so maybe its something to do with that but I'd like to know before i remove it.

If anyone can help identify its use that would be awesome.