Speedo not working!?!

[Kenned4200]

Can anyone tell me what the wires in this connector are?

the problem is as follow

Normal lights in speedo when on acc, but they are on approx half when ignition is on. Take the orange connector out, and they work like normal again? WTF?!

 

[Kenned4200]

 

[Kenned4200]

I know that one of the wires are for rpm's

 

[Kenned4200]

Okay, i have now broken it down to 1 wire.
Anybody knows what wire number 4 does?