Constant 12+ Volt

xxvietboizxx · 10-28-2009, 12:58 PM

Hey guys,

I'm installing a new head unit on my car and I'mpretty new at this. I pretty much got the basic down with the harness and wiring. However, I heard that I need to run a constant 12+ volt to my new head unit to prevent it from resetting everytime. How will I be able to do this? I recall something about a T-Tap. Can someone please elaborate. Thanks in advance!!

mrwink2006 · 10-29-2009, 07:44 AM

Need to know Year of vehicle. Some said I wouldn't get a constant from my harness, but I did. I had to tap into the lighter power wire to get my ACC/IGN power. Get the stereo harness adapter from Crutchfield.

stratplaya06 · 10-29-2009, 09:22 AM

The fusebox has millions of constant 12v sources. Probe with a multimeter until you find one, use fused link, and connect up. Simple!

grimplinyi · 10-29-2009, 11:25 AM

Hy!

an one on button press 12volt where find?

grimplinyi · 11-02-2009, 04:00 AM

where find like that +12volt what there is then when the key is within?

I was searching, but I found one like that where you are constant on ignition +12volt.

xxvietboizxx · 11-02-2009, 08:51 AM

Ok, I ran the constant 12v from the battery to the radio. I did the same with the ground but to the battery ground. Now I have a RED wire that needs to go to the ignition wire. Where can I find that? I thought you can just tap it into the cigarette lighter fuse but when I did that nothing happen and my cigarette lighter doesn’t work. Fuse is not blown either. So I called Kenwood and they told me to connect it to the ignition wire located in the car harness. What do you guys think? As of right now, the red wire is connected to my cigarette lighter fuse using a fuse link. But I have no power at all on my cigarette but everything is else is running fine. Blinkers, wipers, etc.

xxvietboizxx · 11-02-2009, 08:53 AM

By the way, it's an 09 e92 coupe. Cigarette fuse is 08. After many failed attempts testing out the fuses I gave up and went online and finally found out it was 08.

mrwink2006 · 11-02-2009, 11:48 PM

I didn't tap into the fuse box. I tapped straight from the power wire going into the cigarette lighter. You know it only works when the car is on, right?

xxvietboizxx · 11-03-2009, 08:13 AM

Yeah, I might've mess up something inside my fuse box since my dumb self thought I was suppose to wire it to the fuse box. Now I know I was suppose to tap it into the wire that goes into the cigarette light. Basically it's not the brown one, that's going to ground of course, but which wire should I tap it into? There's total of 3, 1 ground, and one is probably for the power but I'm not sure what the other one is. Now I have to put everything back to stock and bring it to the boys at BMW and have them fix my fuse box LOL. Gotta love warranty.

10-28-2009, 12:58 PM	#1
xxvietboizxx Enlisted Member 9 Rep 36 Posts Drives: E92 Join Date: Aug 2009 Location: Houston iTrader: (0)	Constant 12+ Volt Hey guys, I'm installing a new head unit on my car and I'mpretty new at this. I pretty much got the basic down with the harness and wiring. However, I heard that I need to run a constant 12+ volt to my new head unit to prevent it from resetting everytime. How will I be able to do this? I recall something about a T-Tap. Can someone please elaborate. Thanks in advance!!
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10-29-2009, 07:44 AM	#2
mrwink2006 Enlisted Member 3 Rep 31 Posts Drives: 2006 Apline White 325i Sedan Join Date: Aug 2009 Location: Abilene, TX iTrader: (0)	Need to know Year of vehicle. Some said I wouldn't get a constant from my harness, but I did. I had to tap into the lighter power wire to get my ACC/IGN power. Get the stereo harness adapter from Crutchfield.
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10-29-2009, 09:22 AM	#3
stratplaya06 Captain 46 Rep 967 Posts Drives: 2008 E92 335xi-SOLD 5.0 Miata Join Date: May 2008 Location: Maryland iTrader: (10)	The fusebox has millions of constant 12v sources. Probe with a multimeter until you find one, use fused link, and connect up. Simple! __________________ \| PROcede Rev3 \| Vishnu Meth \| DCI \| BMW Perf. Exhaust \| AR Coated/Catless \| CP-E FMIC \| Quaife \|
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10-29-2009, 11:25 AM	#4
grimplinyi New Member 2 Rep 27 Posts Drives: BMW 318d E90 Join Date: Sep 2009 Location: n47 iTrader: (0)	e90 Hy! an one on button press 12volt where find?
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11-02-2009, 04:00 AM	#5
grimplinyi New Member 2 Rep 27 Posts Drives: BMW 318d E90 Join Date: Sep 2009 Location: n47 iTrader: (0)	e90 where find like that +12volt what there is then when the key is within? I was searching, but I found one like that where you are constant on ignition +12volt.
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11-02-2009, 08:51 AM	#6
xxvietboizxx Enlisted Member 9 Rep 36 Posts Drives: E92 Join Date: Aug 2009 Location: Houston iTrader: (0)	Ok, I ran the constant 12v from the battery to the radio. I did the same with the ground but to the battery ground. Now I have a RED wire that needs to go to the ignition wire. Where can I find that? I thought you can just tap it into the cigarette lighter fuse but when I did that nothing happen and my cigarette lighter doesn’t work. Fuse is not blown either. So I called Kenwood and they told me to connect it to the ignition wire located in the car harness. What do you guys think? As of right now, the red wire is connected to my cigarette lighter fuse using a fuse link. But I have no power at all on my cigarette but everything is else is running fine. Blinkers, wipers, etc.
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11-02-2009, 08:53 AM	#7
xxvietboizxx Enlisted Member 9 Rep 36 Posts Drives: E92 Join Date: Aug 2009 Location: Houston iTrader: (0)	By the way, it's an 09 e92 coupe. Cigarette fuse is 08. After many failed attempts testing out the fuses I gave up and went online and finally found out it was 08.
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11-02-2009, 11:48 PM	#8
mrwink2006 Enlisted Member 3 Rep 31 Posts Drives: 2006 Apline White 325i Sedan Join Date: Aug 2009 Location: Abilene, TX iTrader: (0)	I didn't tap into the fuse box. I tapped straight from the power wire going into the cigarette lighter. You know it only works when the car is on, right?
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11-03-2009, 08:13 AM	#9
xxvietboizxx Enlisted Member 9 Rep 36 Posts Drives: E92 Join Date: Aug 2009 Location: Houston iTrader: (0)	Yeah, I might've mess up something inside my fuse box since my dumb self thought I was suppose to wire it to the fuse box. Now I know I was suppose to tap it into the wire that goes into the cigarette light. Basically it's not the brown one, that's going to ground of course, but which wire should I tap it into? There's total of 3, 1 ground, and one is probably for the power but I'm not sure what the other one is. Now I have to put everything back to stock and bring it to the boys at BMW and have them fix my fuse box LOL. Gotta love warranty.
	Appreciate 0 Quote