[Andystobbs]

You also have a major miss match on pins 1 and 2.
There are 3 different trailer modules available.

[KevRum]

Anyone can help me diagnose, I got it from local breaker, i connected everything except the footwell module wire and the CAS module wires. Also I'm currently taking power straight from battery with a little jumper I made.

But the unit is not lighting up nor doing anything in particular, Opening the black plug module I found corrosion inside and on the white plug module there is little corrosion inside the plug . Could this be my current issue of the thing not doing anything and the button light not lighting up, or do i need to connect Footwell and CAS to be sure?

Checked earths , all 3 from outside and 2 thin from modules are grounded into the post on suspension tower (e91) and I'm giving power to each module + the positive coming from outside of the car.

Also the brown/white wire is connected into the junction on the wire bundle near battery ( guess its so the module can tell the boot is open?)

Its 2009 325D m57 automatic and the donor is 2006 330D xDrive Manual

[KevRum]

So i got it sorted, kinda. These wires to CAS and FRM are necessary for the module to wake up and release the hitch. But I was hoping to take power from the rear Cigarette lighter, as its switched and I can have extra Fuze for it. But the problem is, the green light goes off when the car is on, so I cannot release the hitch when ignition is turned on. Currently I'm taking power from the battery with fused wire, but is it really necessary to run them to the fuse box then?

Do yours work with ignition turned on?

[Andystobbs]

No, it only works with ignition off