In search of an ignition wire

**R3l0ad** · 01-14-2004, 10:39 AM

written my first suggestion to you as I am currently in your same position, BUY A MULTIMETER IMMEDIATELY!!! Because if you hook it up wrong, your screwed and you WILL (as I have) fry your ITPS. You must have both a constant 12V coming from such things as an ignition wire... I myself am using the the wire from my HU, then you need to have a wire to the battery. The ITPS requires MORE than 12V its like 13.8V before it will provide 12V to the PSU.

Buy a multimeter, I bought one from radio shack for 15 bucks, it was 15 bucks well invested to measure how much voltage is coming from where. as for a diagram of the ITPS let me hook you up.

The following Diagram is my understanding of how the ITPS should be hooked up. Hope it helps!!

**MatrixPC** · 01-14-2004, 11:18 AM

If you need to buy a multimeter, Harbor Frieght tools has a cheap one. http://www.harborfreight.com/cpi/cta...emnumber=35761.
This one is the same or similar http://www.harborfreight.com/cpi/cta...emnumber=30756. I bought one and I been using it for the pass couple years. It's not 100% accurate at measurement compare to the Flute but it can get the job done.
There are couple place to get the ACC/IGN wire from the car. In general, the ACC is cut off during cranking.
ACC: Cig lighter.
IGN: Power Mirror Control Switch.

**witten** · 01-14-2004, 02:45 PM

Thanks for the ideas everyone. I actually ordered a multimeter last night after I posted the question:

http://www.web-tronics.com/my-68.html

I'll poke around on the head unit for wires, so I guess I'll have to disassemble my dash a bit. If I decide to get either an ignition wire or a constant +12V wire from a plug in the fuse box that already has a fuse in it, I can just wire the fuse in-line and all will be okay?

**[H]Bugster** · 01-14-2004, 04:04 PM

Just a heads up, i tested my cig lighter in my '02 Ford Ranger when the engine is OFF, and the lighter DOES work. So, i think most cig lighters nowadays would be the same. That means, we need (or at least i do) to find a different source for the ignition wire.

**witten** · 01-14-2004, 04:15 PM

[H]Bugster: Well at least you've now got a handy source for the constant +12V and don't have to run a wire from the battery. You'll just have to find an ignition wire source in one of the many places suggested by the people above.

**craigyb** · 01-14-2004, 04:21 PM

I wouldnt use that wire as a permanent 12V to drive an Inverter or DC-DC converter unless they are very low power. 55w=4.6A, thats a lot of current down a thin wire.

As I said in my earlier posts, run the constant +12V from the battery with a large fuse in the way. Get the IGN/ACC from where ever you can, I'm lucky the Merc cig lighter is switched, but my dad's weren't.

I was right about the ITPS it worked just as I thought. So I may order one now.

Craig

**Imy01** · 07-27-2006, 02:29 AM

As I understand it, you would like to find an accessory (ignition) wire in your vehicle. By definition you need a wire that only has power when the ignition is turned on, and when the ignition is turned on you need the 12v feed to be constant. Here's what I suggest...

Take a test light and poke around in your fuse box under your dash a little, you will eventually find several fuses that are only active when the ignition is on. With luck, some of these will not even be in use, so you can use it for your own purposes. There are several ways to use the fuse box for an accessory line, the easiest being inserting some sort of connector into the slot where the fuse can go (I find that certain spade connectors, once modified a bit, work very nicely). Once you create a connector, simply attach a wire, insert it into the slot in the fuse, and you now have your ignition wire! I actually use one fuse location to power 2 amplifier accessory lines AND 2 LED light strips at the same time, so there is plenty of power running from there...

Best of luck to you.