Kill switch wiring help needed: where's the ignition wire?
 

I've seen several excellent posts about wiring a kill switch for racing. I have a 6-pole switch and understand the logic behind it and which wires go where. I have the Bentley manual and the diagram that came with the switch (Smart Racing). I cannot for the life of me figure out where the main ignition wire is. I need to pull it from the fuse box and run it to the kill switch. I've looked at the fuse box map assuming it would show the ignition wire but there's no call-out for a fuse controlling the ignition switch and thus I can't find the wire.

Thanks for the help.

I can't remember off hand, but I would swear I posted my findings in a kill switch thread in the race forum. I'll look for it, but try a search yourself also. My car is the same year, so it should match up easily...

Is this it?

"OK, here ya go! On the fuse box up front at the fuse labeled Backup lights (S11) is the apparently infamous cd box power lead. The top of the fuse panel is the hot side and it is here that the power comes from. On my car, there were two red leads at this terminal. One jumps across to another terminal and the other was trailing behind the fuse box and down into a wire loom. The wire that went into the bundle is the one that I split to eliminate power to the cd box and hence the coil.
It was obviously the correct wire because after it was cut the box quit humming with the ignition in the run position. Also the factory wiring diagrams show this to be the only red wire in the harness that connects to the cd unit."


-Chris

Yep, I was just about to post this..... http://forums.pelicanparts.com/porsche-autocross-track-racing/206658-how-do-i-isolate-coil.html

Good luck!

Thanks.

Now my only problem is I have three wires entering into the top of that fuse. They're all red. One looks like 12 or 14 gauge and the other two look like 16 guage. Which one?

I had two, so your process of elimination isn't much more difficult. Just pull each wire until you no longer hear the cd box with the key turned in the ignition. I'm in Taiwan at the moment, so the top of the fuse box isn't really accessible to check the wire gauge:)
Also check to see which ones go down into the wire loom....

Thanks a bunch, this is a huge help. I'll check it out.

ok so I thought I had this all figured out. I had three wires going into the top of fuse 11: two red, one blk w/red stripe. One of the red wires went under the fuse block and the other was a piggyback that jumped over to the fuel pump fuse.

So I pulled the red wire that went under the fuse block and connected into it and ran it to a normally closed terminal. From the other normally closed terminal I ran back to the #11 fuse and put the wire into the hole I took the original wire out of.

I got everything hooked up as per the Smart Racing instructions and the engine cranks, I smell fuel out the exhaust but it won't fire nor do I get the CDI humming when I turn the key, which is disconcerting.

I thought maybe it was my splicing and hook ups so I disconnected it all and put the original red wire back into the top of the #11 fuse and now I don't get the CDI humming and it cranks but doesn't fire. Clearly I don't have any spark.

Not sure what's going on at this point. I even tried pulling the pair I had on the normally open terminals and switched them with the wires going to the normally closed in the event I had the ignition wires connected to the open switch and it didn't make a difference.

Any ideas?

Just to clarify, you put everything back in its original position and the CDI box won't crank up? Great...
You've probably already done it, but I would clean up the terminal and put a voltmeter on that fuse position to confirm you are getting juice with the key turned. This may be silly, but the cutoff switch was verified 'On" right? I realize the engine cranked, but I'm kinda stumped, so I'm just thinkin' stupid out loud...

I double checked everything and couldn't figure what was going on. Then for laughs I decided to do a resistance test on each wire. I wasn't expecting anything negative because they were simple bare wire crimp-on connections. However, the wire to the CDI box was registering 0 ohms. I made a new wire, installed it and the system tested fine. The kill switch works great at idle and at the mandatory 2000 RPM test.

All is well and thanks a million for your help.

-Chris

Glad to hear it all worked out, good luck on the track!

john cramer helped me out in here about this:
http://forums.pelicanparts.com/showthread.php?s=&threadid=266807&highlight=kill+s witch

Yeah John gives great advice. I read the same one you just linked to sort out my shopping list and it was sooo helpful. His blow-by-blow is perfect and left me wondering only one thing: which color wire and where to find it?

Between ipapilot and john_cramer I'm all set. Gotta love this community!