Need help wiring radar detector into map light

[TWiley]

I have a 2011 z4 3.5i and have installed a BlendMount bracket to mount my radar detector on the rear view mirror. I also bought a power cord from www.mirrortap.com and would like to power my detector from the overhead map lights. Has anyone done this? Attached are Photos of the two wiring plugs attached to either side of the map light unit. Any clue as to which wire would give me 1) 12 volt switched and 2) a ground. Thanks much.

[persian54]

It's been YEARS so don't quote me.. but IIRC, we used brown for ground, and white/green for power.

[Mick70]

Originally Posted by persian54

It's been YEARS so don't quote me.. but IIRC, we used brown for ground, and white/green for power.

I tried exactly the same colors, one year ago for my dashcam. Result: Complete roof malfunction! I am not sure why and if this indeed was the cause, but only after completely removing the cables and even the battery for some time I could remedy the issue.

I have then led a new cable behind the trim from the footrest (wiretapped to contacts of the cigarette lighter, with its own fuse) to the mirror. This is a better solution as I could draw >5A through the new cable without any problems and radar warners can be quite energy hungry.

Best regards

Mick

[mbetoni]

In wiring my SpecDock into my previous E85, IIRC, brown was ground, RED was power - not white/green. However, of course the E89 might be different...

[TWiley]

Use the plug on passenger side of map light. Red post into green-white for switched power. Black post into brown for ground. Thanks to my brother-in-law, a Siemens technician, and his multimeter AND persian54 whose memory was perfect.

[InsanePineapple]

White/green for 12v+, and just any exposed metal that is a part of the chassis for ground. I just taped ground to the metal behind the map light since I had no other way to secure it. No problems.