I am addressing the same issue re wiring to the map light. I sent a PM to another member, and this is what he sent me. Great information.
Originally Posted by wcarter
Ran a search. Hopefully these links will work.
The first one has no pictures but a detailed step by step set of directions: I note that the author tells you how to make your own Y connectors; I used the Lynn Keen method which is a little simpler, using the brass premade Y connectors: http://www.bmwlt.com/forums/showpos...68&postcount=14
This post has pictures of an installation using the same directions: http://www.bmwlt.com/forums/showpos...25&postcount=18
Post #12 on this thread shows how the owner drilled an extra hole near the map light to pass the wiring through. If you are only passing in the Garmin power cable this seems unnecessary to me. You can also see the small hole on the left edge (9 o'clock position) of the map light; this is the hole I enlarged to pass my wiring through. Instead I would cut a new notch at the 12 o'clock position. http://www.bmwlt.com/forums/showthr...ht=light+Garmin
The last picture attached to the first post in this thread shows the Garmin power cable routed through the existing hole beside the map light (like mine): http://www.bmwlt.com/forums/showthr...ht=light+Garmin
Here's a thread with good concise directions (several versions) but no pictures: http://www.bmwlt.com/forums/showthr...ht=light+Garmin
Another with no pix: http://www.bmwlt.com/forums/showthr...ht=light+Garmin
I'd recommend that you gently pop the map light from the dash and eyeball it with one of these posts in hand. I bet it will make sense then. If not, send me another PM; I'll take some closeup pix of my setup and send them to you.
THis is what I originally PMed to wcarter:
Originally Posted by sully2028
Saw your post on the LT Forum. You said "The wiring to the map light has been discussed a good bit, with pictures, on this forum if you want to try a search. If you can't find it, send me a PM."
I ahve searched but to no avail. Can you send info?