Switched 12v supply

[maint]

I'm carrying on reinstalling my dash after replacing the heater core and want to wire a dashcam in. But, because most everything is unplugged I don't want to power up and find a switched 12volt source. Is there a switched source (power when 'run' or 'acc') near the dome light & sunroof or will I need to run a wire down to the dash? The dash is loosely in place and now is the time to run wires if I need to.
Someone backed into the nose last year, 200 kms after a full respray, and claimed he was rear ended. Witnesses heard horn going for 10 seconds before bang but didn't 'see' the hit. Insurance, without eyewitnesses, automatically assigns blame to the rear car. Fought it for a year to no avail. Now the electronic witness runs everytime the car does.

[toomanyparts]

I believe the best place to tap into would be the second black box for the cruise control connection in the rack of three. See page 11 here:

http://www.frankies-bmw.com/8series/...s/EBA_TMS2.pdf

If someone has a better more direct, please let me know. I do not believe the early cars have a 12v source running to the mirror connection (correct me if wrong).

[8eights]

Just get a mirror or action cam, Much easier and they both only record motion. Cheap too!

[maint]

Toomanyparts: the link is in German. Could you tell me where this is?

8eights: bought a Blackvue a week after the accident. Happy with it, added bonus is it's very hard to see from outside. Next liar will get a surprise when the video shows up

[toomanyparts]

Toomanyparts: the link is in German. Could you tell me where this is?

8eights: bought a Blackvue a week after the accident. Happy with it, added bonus is it's very hard to see from outside. Next liar will get a surprise when the video shows up

Disregard that German link - only the V8 models use a switched 12V source there. See 8eights post here instead:

https://www.bimmerforums.com/forum/s...8#post27352618

Looks like pin 3 of the first pinout listing is your closest proper switched 12V source.

[maint]

That helped! Looked at the mirror wiring on Timm's page and it did show switched power. I'll check the actual mirror wiring tomorrow. If mirror option looks good I'll reassemble the dash to the point I can put power to it again. I'll let you know if it works

[supavnick]

That helped! Looked at the mirror wiring on Timm's page and it did show switched power. I'll check the actual mirror wiring tomorrow. If mirror option looks good I'll reassemble the dash to the point I can put power to it again. I'll let you know if it works

on my 91 850 i have installed later model rear view mirror:
3-pin yellow connector:
brown -negative
white/blue - reverse signal
third wire is switched 12v - can't recall a color (red/green?)

[maint]

Finally got it all back together and running. The mirror has 3 wires running to it; Brown/yellow, Blue/yellow and Purple/white. As Supavnick says, the third wire, the purple/white is 12v switched. Very easy to run a short lead from near the courtesy light under the headliner to a dash cam.