Hey guys,
I'm installing a remote start, and I never really thought about what all the wires do. I always wondered why there are TWO 12 volt wires, both fused. Why not just use one? Is it OK to splice into the same wire twice for them?
Thanks,
--mindctrl
It depends on the car you are installing the remote start in...
If you have two constant 12v wires going to your ignition then you should have one wire on one constant and the other wire to the constant.. However if you only have one constant going to the ignition then both wires can be hooked up to this wire.. As I said it depends on the vehicle and the application..
Good luck J
Ok here's the deal. There are normally 6Ignition wires on a given R/S unit... naturally some have more outputs (acc2/ing3) and some have less.
12V+ Input ~ Supplies the ING/ACC/Jumperable with a steady 12V+
12V+ Input ~ Supplies 12V+ for Starting also powers on board relays ext
Starter Output ~ Output of 12V+ High Amperage to crank the vehicle
ING Output ~ Output of 12V+ to supply the ECM/Ignition system/Fuel system with power
ACC Output ~ Output of 12V+ to supply the blower/climate controll power
Selectable (ING2/ACC2/Starter2) Supplies 12v+ to whatever its jumpered to.
Some vehicles require more... Older fords for instance require 3 ignition wires because of the very very high current draw for the blower motor. Simply tieing this wire into the other ACC wire will do no good because now your overloading the system. Good rule of thumb with hooking up ignition wires is: If the wire your hooking up is the same size as the wire tieing into, no other wires should be connected here.
In other words, 1 R/S wire PER 1OEM vehicle wire no matter what. And if you cannot find a 2nd 12v+ wire in the ignition harness, you will not find another useable one under the dash.. yep.. seen this: "Oh.. only 1 ignition hot-wire? thats ok... i'll hook this one up at the fuse box" hahaha
Worst case, you run 1 extra wire through the firewall and connect directly to the battery.
This may be myth or not, I have never seen it happen but have heard stories of a bad unit install drawing too much power away from the ECM/BCM setting air bags off because of the voltage spike it sees. Even if its false, you still run the risk of burning a wire up and possibily catching the car on fire OUCH
-------------
The 2 seperate power wires are usually a main power wire for the unit, and the other would run your ignition wires. You'd see if you pull the fuse out of one of those wires some of your unit will probably still work. If so that fuse is most likely for your ignition wires. If you pull a fuse and the whole unit seems dead than you pulled the main power fuse..
Nine times out of ten you can tie both of those wires into the same 12v power wire and not have to worry. That 1 time it isn't enough, you can run a lead to the battery or to a thick power wire from the fusebox. In any event if there is more than 1 power wire at the ignition harness, you should hook your wires to each one.
Most GM's will have at least 2 thick red constant wires (or a red and a RED / white) at the ignition harness. Ford's usually have a couple yellow and some GREEN/ violets. Chrysler commonly has the pink/black and red constant wires.
Offhand the only cars I don't use the constant at the ignition harness are on escapes and caravans. Escapes I use the thick yellow at the fusebox in the driver kick, and on caravans I use the thick WHITE/ red in the driver underdash area. Also usually on LeSabres I run a wire to the battery..There's probably a few more oddballs I'm missing. Hope that helps,
Mike
if you look at the fuse rating on the red wires they are usually 30a. so if you tied them together then you could be drawing 60a through one 12gauge wire, plus any constant power you need for relays and bypasses ect. now thats only max power and most likely wont happen unless there is a short, but they give you two, so use them.