Starter Interup Wiring Question

i am looking at the starter interup diagram. on this diagram it says to go to the horn positive. is this the wire that goes from the relay to the horn? and the horn relay positive.so am i cutting the wire that goes positive to the horn? or am i hooking to a totally different spot? on the 12 volt ignition terminal--does this need to be on a wire that is positive when the key is in ignition and start mode? and? why does the exciter wire for the coils on the relay's tie in with the componenet or wire that actually sends the signal for the coil? i just bought a new truck and this is an intruiging starter kill. i just want to understand it a little better.i have wired asll kinds of relays up but havent used diodes for the hook upand i am thinking that that is whats confusing me as to how it works. please give any and all feedback.

https://www.the12volt.com/images/hornstarterkill.gif

It does appear that you are cutting the positive wire from the horn relay to the positive side of the horn and rerouting it thru the relay at the lower left.  This is so when you press the horn to deactivate the passive starter kill, that it doesn't sound the horn, it only supplies 12V to the relay in the upper right to latch the relays and deactivate the starter kill setup. But you have to have the ignition key in the "on" position first, before you press the horn.

The ignition 12v(+) can be tapped to any circuit that is controlled by the ignition switch "on" position.  The wire from the ignition switch to the starter also needs to be cut and rerouted thru the relay in the upper left corner. The exciter wire on some of the relay coils from the components is wired to initially activate the relay coil and start the latching process.  The diodes are shown to allow power to flow one way and prevent power from backfeeding into unwanted wiring once the relays are latched.  You could probably use 1N4001 diodes where indicated.

Personally, I wouldn't like using the horn to deactivate this relay setup, I think it would be a PITA and get old quick having to press the horn each time prior to starting the vehicle, plus it may present a problem when you take your vehicle in for an annual state inspection.  The horn is actually deactivated and will not work when the key is not turned on, and then it will not work until the second time it is pressed. Once you turn the vehicle off, the horn is deactivated.  Of course, you could wire this setup so the horn is not deactivated when the vehicle is off, but the horn would blow when you pressed it to deactivate the starter kill circuit, which is defeating the purpose of the original diagram.

I would personally rather substitute using the brakelight switch to deactivate the starter kill.  If you wanted to use the brakelight switch, you would have to press the brake pedal and hold it while you started the vehicle, but this setup would only require one relay and you would only need to cut the starter wire.  If you have cruise control buttons on the steering wheel, you could possibly press the cruise control "on" button to deactivate the interrupt, you could actually use any positive switching accessory, that would be convenient, to wire up a starter interrupt using with only one relay. 

Maglin, if you want to interrupt the power to the "on" side of the ignition switch, it would probably be better to run the power for the "on" feed thru a relay instead of a hidden switch. If you only used a switch to interrupt this circuit, it would have to be a rather large switch rated to carry a lot of amps. However, you could use a small mini switch to turn the relay on and off, which would connect or disconnect the ignition "on" power. The smaller switch could be more easily hidden.

The best hidden switch setup I've used was a small, push on push off switch mounted at the bottom of a dummy cigarette lighter housing.  The knob portion of the lighter had the heater coil removed so it could not touch the hidden switch. You would pull the cigarette lighter knob out, stick your finger in the lighter housing socket and push the on/off switch to activate a relay that controlled the power to the ignition switch.  Then you would simpily put the lighter knob back into the socket to hide the switch from prying eyes!  If a car thief is looking for a hidden switch, he probably isn't going to expect it to be inside of the cigarette lighter!!

one04fx4,  the dei 528t looks to be a pulse timer relay, you would activate it with a (+) or (-) pulse, probably as quick as less than half a second, then it would latch and not unlatch until the user determined time limit(0 to 90 seconds) expires.

You can use this relay to activate or deactivate circuits for a preset time limit, but  I'm alittle unclear on how you want to incorporate this relay into a starter interrup circuit?