+12V ONLY with engine running?

gchristopher9

Member
Location
Boston MA
I am looking for a wire that is only at 12V with the engine running. I want to use this to power relays through switches for my angel eyes. i dont want to them to come on with ACC because this ACC goes to zero when the engine is cranking. this would mean if my angel eye switch was on, the angel eyes would come on when the key got to ACC, then turn off whilethe engine is cranking, then turn back on when it actually kicks over. this on-off-on cycle is a no no when it comes to things like ballasts and inverters. i am hoping that is a wire that only goes to +12V when the motor kicks on, but stays off when the key is in the accessory position. anyone know where i can find this?
 
Test this wire here, (taken from the stillen site)

If I remember correctly this is a +12v (engine running). This was the location for installing the stillen intercooler pump.
 
check the left side kick panel, I know there are wires there that can accomidate you, just don't remember the exact one, I'll try to drop my left side kick & tell yoiu which I cennected to, needed this for dash illumination on the 06^ cluster...
 
just wondering, but, what's wrong with just tapping an ignition hot wire?

ah........just read the entire post after i posted. i get it.

for the police cars we use a company called charge guard that will power up with ignition on, but, once it senses ign. 12v there is a 10 second (adjustable) delay before it will power the accessory. maybe you can check out their options and go from there. i think it may be what you're looking for without the p.i.t.a. of an engine only 12v source.
 
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that is what i'm looking for an ignition hot wire. so my accessories only run when the motor is running. i dont want to run them from ACC 12V because when i put the key in they will turn on, then off while the motor is cranking, and then back on once it has started. this on-off-on cycle will destroy aftermarket HID ballasts and probably angel eye inverters as well. i want them to stay off, until the car is actually running. i wouldn't mind being able to power them with ACC, but then i would need some kind of delay or somethign to keep them on when the motor is cranking, because ACC 12V turns off while your cranking.
 
the headlights actually power up if you set them to auto-on....

they'll get constant power while you are cranking the engine, but, there's some amperage loss obviously while cranking. if anything, try tapping into the lights since it is lighting anyways. this won't destroy the ballasts.
 
i've heard very bad things about turning cheap aftermarket HID ballasts on and off quickly. i would like to prolong mine for as long as possible.

i dont mind having to run the motor to turn this stuff on though. can't imagine any instance where they would need to turn on with just ACC

---------- Post added at 02:53 PM ---------- Previous post was at 02:52 PM ----------

baker shouldn't your KP technologies fog module keep the fogs on whenever the switch is on?
 
for the most part, ignition and accessory are pretty similar, but, i know where you are going with this.........

check out that charge guard place maybe. if they had something for you, you could tie in to whatever you wanted and set the dc delay to whatever you wanted. 10 seconds would allow you to turn the key and start the vehicle and a few seconds later, they'd get powered and light up. imo, it's overkill and i think you'd be fine without it, but, if you want the extra security measures, that'll work for you.

i've had my aftermarket HID foglamps for about 2 years now. i never turn them off for the most part and they power up with my headlights in the morning, etc. when i leave for work at o'dark 30 every day. the ballasts fire up before the engine cranks (with the headlights) and i've never had a problem with them. i paid $200 for the 2 ballasts and 4 HID lamps - 2 headlight and 2 fog. they're not cheap, but, they're by no means expensive.

i think you'll be fine tapping into the headlight circuit tbh. if you're still worried about the ballasts blowing, spend a few more bucks on ballasts. they're pretty durable. i would think that the road vibration and summer heat/winter cold do more to them than the voltage changes.
 
ign will power up when the ign is fully on & it will maintain power even when you crank... acc will power up in either acc or ign, but the power will drop as you crank...

worse case there is always a ign lead at the ign switch, but heavier ~8 gauge wires & harder to tap... last resort...

if you want ign then that's pretty easy, if you want true only powered when running though, in other words still not powered even with ign on, but only when the car is really running idle or above, this will take either a voltage sensing circuit or a tach sensing circuit, I'm guessing you really mean ign & not truely "only when running"...

I'll take my kick apart later & show the wire I used...
 
yea i mainly just need something that comes on, and stays on, even when the motor is cranking. I'll trust that you know what I'm talking about by this point and go with your recommendation in the kick panel.
 
i've heard very bad things about turning cheap aftermarket HID ballasts on and off quickly. i would like to prolong mine for as long as possible.

i dont mind having to run the motor to turn this stuff on though. can't imagine any instance where they would need to turn on with just ACC

---------- Post added at 02:53 PM ---------- Previous post was at 02:52 PM ----------

baker shouldn't your KP technologies fog module keep the fogs on whenever the switch is on?




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the HID kit i have now is the more expensive one, around $500 as opposed to the $80 i used to have haha. and yeah, they are on whenever the switch is on, but if i put the car in ACC for a bit, then turn the engine on, the fogs and my ipod thing turn off then on quickly. I'm sure it's not abnormal behavior.:tongue:
 
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