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Wiring Aftermarket Ignition Switch

6
3
Exp. Type
HPDE
Exp. Level
Under 3 Years
Georgia
Hi all,

My friend and I are currently building a 2000 GT for 24 Hours of Lemons/Champ Car endurance racing. We've ditched the stock column in place of a QuickCar switch panel and a Joe's kill switch and I need some help with wiring. As it stands now, here is the wiring setup:
  • Positive battery cable to kill switch;
  • Alternator to kill switch;
  • Kill switch jumper;
  • Kill switch to QuickCar panel;
  • Ground from QuickCar panel to roll cage;
We disassembled the ignition switch and have the following colored wires:
  • Green w/purple stripe
  • Green w/purple stripe
  • Red w/green stripe
  • Red w/black stripe
  • White w/pink stripe
  • Black w/green stripe
  • Grey w/yellow stripe
  • Grey w/yellow stripe
  • Yellow
  • Yellow
  • Yellow
We've tried combining these in different ways to get the "Ignition" switch on the QuickCar panel to essentially be like turning the key to "On" and hitting the button on the panel to be like turning the key to "Start" and cranking the engine over. Not matter what combo we use, the gauge cluster illuminates the ABS light and the turn signals simultaneously (they are not blinking) and we can get the engine to turn over but we have no fuel pump, no dash lights, and I'm assuming no spark. My friend and I are both mechanically inclined but are nowhere near electricians, so we're throwing up the white flag on this and asking for help. If someone could give me a rudimentary wiring schematic for this that we could try and recommend any relays or other switches we'd need, that would be greatly appreciated. We do have the stock column available and have the anti-theft plugged in using the key, we're planning on disassembling that and mounting it under the dash once we get everything painted and assembled. We want to hear it run and get all of our connections made before we disassemble and paint. Thanks in advance for any help with this!

-Mark
 
Very excited to see another sn95 budget racer on the board! Welcome!

I left my stock column in place so im not sure how much i can help. I have been tempted to rip out the stock stuff and replace it with a simple push button so excited to learn from your experience. I know the pats system is sensitive to the key being in that black ring with the one wire running from it.

I feel like the kill switch wiring is the most widely debated topic on the lemons forum. I prefer the ones with alternator protection. I guess if the alternator is spinning without a place to dump the load generated it will ruin itself. Or thats what i read on the internet :)

I believe this is the one i got

The big terminals are as you expect battery on one side and everything that needs juice on the other. I think i left the alternator on the “needs juice” side.

The little terminals are supposed to cut the ignition coil. My method for identifying that was
1) get the car running
2) disconnect battery +
3) car should still be running from alternator
4) start pulling fuses one by one until i found the one that killed it instantly like i wanted.
5) wire the small z terminals in there

good luck!
 
70
79
Exp. Type
Autocross
Exp. Level
5-10 Years
Virginia
This is something that I need to do as my key switch broke. I removed the ignition switch and just move the post manually to start the car. But it's mounted under the dash and is hard to reach when strapped in.

As I haven't yet sat down and figured out the wiring, I can't answer your question right away. I will look over the schematic (hopefully later today) and figure out how the switch works. It does have a lot of wires going to it.
PXL_20210409_233931750.jpg
 
70
79
Exp. Type
Autocross
Exp. Level
5-10 Years
Virginia
So my ignition switch (1994) has different colors than you listed. Do you still know where the wires went on the ignition switch? It doesn't seem to be as easy as just connect these wires and everything will work. Unless you were still using the key and just wanted a push start button. Since you said its for a race car, I'm sure can simplify the wiring a lot to just a few wires.

Here is are the colors used on my ignition switch and some of the functions. The schematics in the manual are missing a detailed layout of the ignition switch.
Wire ColorIgnition Switch PinFunction
Black/BlueA1Hot in Run or Acc Output
Grey/YellowA2Hot in Run Output
Grey/YellowA3Hot in Run Output
Grey/YellowA4Hot in Run Output
YellowB1Battery Input
YellowB2Battery Input
YellowB3Battery Input
YellowB4Battery Input, Ign Sw Fuse 40A
YellowB5Battery Input
Tan/WhiteI1Hot in Start or Run Output
-I2Not Used
Purple/WhiteP1Grounded in Start Output, Illuminate Brake Indicator during START
Black/BlueP2Grounded in Start Output, Illuminate Check Oil Indicator during START
White/PinkSTAHot in Start Output, .Starter Relay Coil, connects to B4 during START (goes through clutch, anti theft, and transmission range before start relay)
BlackGNDGround (only used for P1 and P2 during START)

From the manual here are the continuity checks for the various key positions:
Key PositionContinuity BetweenContinuity Between
ACCB5A1
LockP1P2
OffP1P2
RunB1A1
B2A2
B3A3
B4A4
B5I1
StartB1I2
B4STA
B5I1
P1GND
P2GND

Lastly, this post I found very helpful. Make sure to read to page 2 as the diagrams change a bit.
https://www.sn95forums.com/threads/ignition-switch-wiring.71850/
 
70
79
Exp. Type
Autocross
Exp. Level
5-10 Years
Virginia
Chandler, did you get your ignition switch figured out?

I'm in the process of doing this right now, here is what I'm going to do. I bought a universal ignition switch panel from Amazon. It has a On/Off switch, push button start, and two accessory switches. I also bought 4 relays. The switch portion of the relays will connect the yellow and grey/yellow wires. The coil portion of the relays will connect to the panel. The On/Off switch will be my Run circuit (still need to figure out which wires need to be on to run). Then the accessory switches will turn on my accessories, ie circuits not needed to run the engine. The start button will connect to the white/pink wire for the starter.

You could use switches in place of the relays, but could be a lot of current depending on what you're running (supply fuses are 40A). Also so not to extend all of the ignition switch wires I can mount the relays under the dash and run the coil wires to the panel.
 

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