12V+ Switched in Trunk for DSP

TechieCarGuy · 02-18-2016, 01:51 PM

I've got my trunk torn apart awaiting the delivery of a Digital Signal processor to handle the audio processing for the continuation of my audio upgrade and while I do have a fairly nice multi-meter am being lazy and thought I would ask instead of doing the work myself.

I did a search and didn't find anything specific to our cars, but am looking for a switch 12v+ and a constant 12v+ in the trunk, specifically in the center area behind the seats (were I think the Sat. Radio receiver would go).

My car came with Base stereo, so there is no amp in the trunk, this no harness to tap into and I do not think I saw any other harnesses. I'd like to find a good switched source for my DSP without having to wire up a relay(although this is usually the safest route). I also have the right side of the trunk torn apart so there might be something there.

I found a post on the F30 forums that discuss a Black/red as switched and red/green as constant, but am at work and can't look to verify.

Thoughts?

TechieCarGuy · 02-22-2016, 10:07 AM

I ended up running a wire from the cig lighter/12v outlet under the console arm rest. Was easier to snake a wire back to where I needed it than spend a whole bunch of time with my multi-meter trying to find a wire.

reisf · 02-23-2016, 06:06 PM

Where are you getting your constant 12V from?
For switched 12V most people use pin 13 on the back of the head unit harness and constant 12V is taken from the battery with an inline fuse
here:

and grounded here:

02-18-2016, 01:51 PM	#1
TechieCarGuy Private First Class 134 Rep 170 Posts Drives: 2011 E91, 2008 Z4 Join Date: Nov 2015 Location: Florida iTrader: (0)	12V+ Switched in Trunk for DSP I've got my trunk torn apart awaiting the delivery of a Digital Signal processor to handle the audio processing for the continuation of my audio upgrade and while I do have a fairly nice multi-meter am being lazy and thought I would ask instead of doing the work myself. I did a search and didn't find anything specific to our cars, but am looking for a switch 12v+ and a constant 12v+ in the trunk, specifically in the center area behind the seats (were I think the Sat. Radio receiver would go). My car came with Base stereo, so there is no amp in the trunk, this no harness to tap into and I do not think I saw any other harnesses. I'd like to find a good switched source for my DSP without having to wire up a relay(although this is usually the safest route). I also have the right side of the trunk torn apart so there might be something there. I found a post on the F30 forums that discuss a Black/red as switched and red/green as constant, but am at work and can't look to verify. Thoughts?
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02-22-2016, 10:07 AM	#2
TechieCarGuy Private First Class 134 Rep 170 Posts Drives: 2011 E91, 2008 Z4 Join Date: Nov 2015 Location: Florida iTrader: (0)	I ended up running a wire from the cig lighter/12v outlet under the console arm rest. Was easier to snake a wire back to where I needed it than spend a whole bunch of time with my multi-meter trying to find a wire.
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02-23-2016, 06:06 PM	#3
reisf Lieutenant 128 Rep 525 Posts Drives: LBB M2 Join Date: Sep 2014 Location: Sydney, Australia iTrader: (0)	Where are you getting your constant 12V from? For switched 12V most people use pin 13 on the back of the head unit harness and constant 12V is taken from the battery with an inline fuse here: and grounded here:
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