Ignition Switch Wiring

TurfBurn

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'01 Yellow MP3 #1026
I've searched high and low for 3 days now, so don't even start to give me the newbie search crap... so now with that said! :D

I need to tap into a wire for running a power relay that will ONLY be on when the car is ON, not in accessories mode, only in true all out ON mode.

Additionally any pointers in getting that steering column cover off would be cool.

I don't believe there is a wire in the stereo harness that is only on when the ignition is truly on. I originally intended to run it purely off of the red "accessories" wire in the radio area, but that won't work for what I need. If anyone can help out on this that'd be fantastic.

I just need a location and the coloring of the wire and I should be good from there.

Later.

Steve
 
Well I worked around for a while and finally found the solution.

So now this is a semi "how to" thread.

The correct way to wire gauges and so forth is to make sure they run on their own power circuit and have enough current. My PLX wideband draws enough current that I couldn't even get it or the radio to turn on when I had it tapped in on the red accessories wire for the radio.

Also gauges really should not be able to come on when the car is in accessories mode. They should only come on when items like the fuel pump comes on and so forth. So essentially the next click past accessories mode and where the key is normally when the car is actually running.
 
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Take the cover off the steering column. Pretty simple, take three screws out from the bottom and then snap it apart. There is no trick to it, just pull until it seperates. Don't use a screwdriver.. it marks up the plastic pretty badly.

Once you do that you'll be able to see the casting that is the ignition switch housing. On the back of that is a very large connector. Either on that connector or on another nearby you'll see a shiny plastic sleeve. If you pull that sleeve back you'll see a bunch of rather large wires (12 gauge in fact). You should see a blue with white, a black with white etc etc. The one you care about is the black with red strip wire. Cut the shiny black sleeve back a ways and then trim off some insulation from the black with red wire so that you have enough copper exposed to make a good solder joint. Otherwise cut it and use some good crimps to make your connections. The wires are large and short, so there really isn't much room, and hence I recommend just trimming some insulation and then soldering on. Tape that all up and you are good to go as far as tapping into a decent "ON" switched 12v source.

Take that and run it to the activation post of a 4 post auto relay (you can get one for like 6 bucks from radio shack). Then you should run from the battery through the firewall another wire of your own to supply 12v current as it's own complete circuit. Make sure you fuse it near the battery just to be on the safe side. I fused mine at 25 amps which is excessive for gauges, but hey :). Run that to the source post of the relay. Then of course run a short wire from the ground post of the relay to a nice screw on the chassis somewhere under the dash. Then last you can run whatever wire or gauge you want to the output of the relay. Each of those posts is labeled well when you buy the relay. No big deal. You can also run to a terminal block or the like under the dash so that you have an easy place to tap into any time you need a switched 12V supply.

That's about it. PM me if you have questions.

Later.

Steve
 
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Okay, I'm really not trying to be a smartass about this, but you're coming off as kind of snobbish. I'm sorry that we're of no assistance to you, and I'm pretty sure it's mostly that you didn't know the name of what you're looking for, but it's pretty common for alarms, especially remote start. Umm, are you sure you looked?
http://protege5.com/vbb225/showthread.php?t=9965
"2nd Ignition, black/red, +, Ignition Harness"
This can be accessed under the dash as well without the potential problems of taking apart your steering column. It's a rather large wire, and it runs from the steeringwheel column area back and then loops up and into the depth of the dash but there's plenty of room to get to it back there. You can remove the trim panel underneath the steering wheel to get even easier access.

Props to you, however for figuring it out on your own. FTR, it generally takes a couple of hours to get a response on here, sometimes a day or 2 for the really informative ones to come around to it, so it's always best to ask any questions you think you might have a bit in advance.

oh, and also, unless you're running anything else off of your power supply, you should figure your current draw form the gagues and fuse accordingly. I always err towards the too small side as far as fuses go. The bigger the fuse the more nervous I get because the more voltage will spike before it pops. If you've ever gotten curious and shorted out a couple of different fuses to test this, you'll know what I mean. a 15a fuse kind of pops, get up over 100 or so and it gets VIOLENT. They serve as fire protection in case of a crash, yes, but with the added bonus that they protect your expensive equiptment, and if something goes wrong and voltage spikes, that extra 15amps or so might just be enough to fry your goodies instead of simply popping a fuse. I'd personally much rather replace a couple of fuses and re-wire of elsewise figure a loose connection or something than ruin equiptment and risk spark or fire damage from whatever arcing might've happened.
 
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Well I didn't expect a response immediately, but I did hope. I didn't intend to sound like an ass, but I see how my posts could have been interpreted as such, so I cleaned things up a little so it doesn't look quite as bad.

Yes I did actually read through that post you indicated among the many many others. But "2nd Ignition" didn't really correlate to "running position" or "ON" to me... I was also pretty concentrated on the "switched 12v" concept so that didn't help. Thanks for linking that thread in though.

Yes I believe you can also access the wires by popping the trim panel alone. I just found that trying to get in at it from above instead of laying on your back the entire time was easier when the bottom column trim was off. Should be pretty safe as there isn't anything major associated with that bottom trim.

The way I have the system fused is purely to prevent a power short. There is also some other stuff running on that line I spliced into under the hood so hence the 25A. But I'd probably recommend like 10A or something for the system otherwise. Overkill isn't necessary. But it also depends on if you are fusing for a short, or fusing for the items on the line.

Thanks for the help!
 
No prob man, wasn't sure you intended it or not. I just kind of took it a bit thatway, figured I'd likely be more civil about it than some of the guys inhere. As for the wiring, I'd imagine the gagues themselves are fused as well, yes? Honestly I hate running extra wires through my firewall. I Prettymuch run all of my accessories off of my Distribution block for my amps.

And yea I kind of figured that terminology might be the confusing bit. Again, it's something usually used for alarm systems. And personally, I'f found that it's actually pretty comfy to just lean my seat back and lay on it upside down while under the dash there. But really I'm kind of paranoid about pulling apart my steering column surround since a friend did his once and it just never went back on right. looked like a stolen car.

Anyway, glad you got it all wired in. How's it work? I'd assume it's for illumination of boost gagues and such? is it a pillar? And while I'm at it, how long have you been turbo'd? do you think it's worth it?
 
Noticed you were more civil than some of the posts that happen on this forum. Some people really go nuts on those that take the time to write up how they did something. Makes it not all that worthwhile to do the writeup if you have to spend a bunch of time defending your work or something :).

I don't think any of my gauges are fused themselves, but their controllers probably are. Most of them are so low of a current draw that it doesn't really matter I think. This wideband is just different I guess. Probably because of running the heater and stuff that is needed for a wideband O2. Running things off the distribution block is a good and easy way. I hate running tons of wire as well, so that's why I tried to just do it straight and right and that way I wouldn't have a mess under the dash or in the engine bay as well.

Certainly had never heard of the "on" position as being called 2nd ignition. Always learn something. My car has racing seats in it, and they do recline, but I've never found out how far yet to see if they are comfortable to lay on. I've had the car for about 2 or 3 weeks now. It's Terry's old car, (spoolinmp3). But I've spent a little time with my brother Little Beavis the last few months helping on his car and so forth, so I've learned some to deal with the turbo stuff.

The boost gauge, old narrowband, and the EGT gauge were all wired in by Terry. The EGT sits on centered behind the steering column. Not a bad position, but blocks the odometer, and it's not really the gauge I look at the most anyway. Then the boost and narrowband are in the old "storage" pocket above the environmentals and below the radio. They look pretty good there. I put the wideband that I wired in where the ash tray used to be, and will put my custom J&S safeguard display there as well. The power circuit I wired in is purely for supply gauge power for now. I'll probably do something similar for illumination. I'll power it off this new power circuit as well. That way less wire running, and since I sized the circuit to 20 amps more or less I should be good for current.

Part of the whole thing that made this complex is that gauges really shouldn't be run off accessory mode, only should be on when the car is actually on. For example, does it make sense to have the fuel pressure gauge running when the fuel pump isn't?? :D. But it's actually important with the wideband, as the heater in the O2 will get run when the controller is on, and it is necessary that it be on when the car is running or you will foul and eventually ruin your sensor. So wiring gauges can be kind of important. I'm still learning, but trying to do things right.

The turbo in this car is amazing. It's running really rich because of the cold weather for safety sake, but it is ridiculously fun. I have lots of good plans for the car over the next year. Keep an eye out ;) Especially next spring. I bought the car because of the autocrossing and some of the high speed racing I'll be doing. Wanted a good car for that. I'd say it's worth it. But you need to have a lot of free cash and a lot of patience to deal with all the hickups. As things get ironed out more and the knowledge base on here grows it'll get easier and easier.

Have a good one!
 
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