IGN or ACC wire?

**zzachattack2** · 04-15-2006, 01:29 AM

Is there anything wrong with connecting amp remote-on wires, headunit power or any other component to an ignition wire opposed to an accessory wire? I know head units are almost always connected to the accessory wire. But if possible i'd like to just use the ignition wire for everything.

**Bugbyte** · 04-15-2006, 01:33 AM

I presume you mean the headunit power on signal wire, right? You don't want to connect HU power to that wire.

The IGN and ACC wires usually differ slightly in function. The IGN wire isn't hot until you start the car. The ACC wire will usually go hot if you turn the key to that position. On my car the ACC wire stays hot until you pull the key out of the cylinder.

They're pretty similar.

**zzachattack2** · 04-15-2006, 01:41 AM

By ignition wire i mean the wire that is hot as long as the key is in the cylinder, even through the cranking cycle. By accessory wire i mean the wire that is hot as long as the key is in the cylinder EXCEPT during the cranking cycle. Most installations have the head unit connected to the accessory wire (explaining why the stereo goes off when the car starts), and that in turn makes the amp remote-on indirectly controled by the accessory wire as well.

Mainly i just need to know if its okay to let amps, head units, etc which are usually halted during the cranking cycle, continue to be on during cranking.

**Bugbyte** · 04-15-2006, 01:43 AM

They will draw down your voltage while cranking.

**Cube** · 04-15-2006, 08:36 AM

Originally Posted by Bugbyte

They will draw down your voltage while cranking.

And horrible changes in current for whatever's being powered at that time

**madkad** · 04-15-2006, 09:46 AM

I would conect all remote-on wires to somthing that only comes on when the ignition is on but not to the direct ignition cable

**Cube** · 04-15-2006, 09:59 PM

Originally Posted by madkad

I would conect all remote-on wires to somthing that only comes on when the ignition is on but not to the direct ignition cable

Not 100% positive, but I do believe there is nothing electrically isolating the two things you speak of... they'll probably have some changing currents as the starter (very large electrical load) is drawing power from the battery...

Again, not 100% positive... so if you know that there's a relay that's electrically isolating the starter from IGN powered sources... please correct me.