Can you help us wire a kill switch for our 1994 Mark VIII Lemons project

phyveaux

Registered
All, we are closing in on the finishing touches for our 24 Hours of Lemons 1994 Mark VIII. We need to wire our kill switch. We will be wiring according to the recommended directions below from the Lemons forums. We have a 4 post kill switch. Two large posts will interrupt the battery. Two small posts need to interrupt the hot lead going into the ignition. Unfortunately, I don't know which wire this is. There are 3 or 4 hot wires when you use a volt meter to test. One of these is the hot going in, probably the others are the starter, accessory etc. as mentioned below.

LOD won't let me upload picture, because it says I've exceeded my quota? Pic of the pins and the harness are at:

https://drive.google.com/open?id=0B58DltRFzCOvbjgzaE9RTEtCTFk

https://drive.google.com/open?id=0B58DltRFzCOvRWp1OEtnNHJpQ1U

Can anyone look at the pins and let me know which one is 12V hot in? This is the one I want to interrupt from the battery. The picture shows the labels (A1, B1) etc. If I can know which one is 12V in, I can figure out the matching wire. I thought I had a good spreadsheet with this info from an alarm installation site, but it isn't detailed enough. Any help would be very appreciated.


These are the instructions from Lemons Forums:

This is how I have wired at least 4 different cars without ever killing an alternator using (mostly) the factory wiring harness and always in compliance with LeMons technical regs. IMHO, YMMV, associated disclaimers apply.
0. Remove the negative wire from the battery. Don't electrocute yourself.
1. Get a 4-post kill switch. I like the Longacre waterproof, since it always seems to rain sometimes at a Lemons race, but there are others out there. Mount it somewhere that (a) your drivers can reach when belted in, (2) that a corner worker or EMS can reach from outside the car and (3) where you can remove it easily because it's easier to attach cables to the back of it when it's not mounted.
2. Figure out the factory ignition circuit. Most cars have one hot lead to the ignition and then a couple of hot outs: one that goes to the starter circuit, one to the run circuit, one to the acc. circuit. You only care about the hot power going in. Cut that line somewhere convenient, giving yourself plenty of wire on both sides. You now have two cut ends. Connect one of those new ends to a new wire that you run to one of the small posts on the kill switch. Repeat from the other small post to the other cut end. I suggest using crimp connections and not wire nuts, but it's your life. This is the connection that will kill the ignition just like the factory does, and using the factory-figured-out method for not nuking alternators.
3. Find the thick + lead from the battery to the engine. Splice that with new wire to the larger kill switch posts in a similar fashion to the instructions in paragraph 3. This is the connection that will kill ALL POWER in compliance with Lemons technical regulations.
4. Re-connect the negative battery lead.
5. Test.
6. Rejoice, or alternatively, despair and try again until you reach joy.
 
Back
Top