5 replies to this topic

[Jack BRCG]

hi iv just got a 12v kill switch (2 pin)
iv seen people wire them in all different ways.
im wondering, which part of the mini circuit is it best to be fitted in??
thanks

[dklawson]

There are several possible places and ways to use your kill switch and you will see several suggested on this board.

One method is to place the switch in series with the current flowing through the ignition coil. A second method is to wire the switch between the coil (-) terminal and earth. Both methods work and both require that the switch be rated for over 5 Amps, preferably 10 Amps or more. If you have an electric fuel pump, a third possibility is to place the switch in series with the fuel pump wiring. As with the first two options, this requires a switch rated preferably for 10 Amps or more.

Is one better than another? It depends on who you ask and what their preference is. The switch in series with the coil power is nice in that it prevents current from flowing at all so a would-be thief who fails won't leave the coil energized and hot which can lead to its premature ignition failure. The switch connected to coil (-) is nice in that its wiring connection can be made using the tachometer sense wire instead of making a connection at the coil itself. That makes concealing the installation very clean and easy. Interrupting power to an electric fuel pump works and has a comic aspect to it. A would-be thief will be able to start a car with carburetors but only drive a short distance before running out of fuel. Of course this will be annoying and embarrassing for him/her but it also means your car may be left in the middle of the road somewhere when they abandon it.

[Jack BRCG]

thank you for your reply. il have a go at fitting it soon, probably between the coil - and earth.
shame i dont have an electric fuel pump. but someone stole my mini momentarily a few years ago and left it in the middle of a road about 5 meters from where i parked it. not sure why they didnt get any further. but it goes to show a loud exhaust is a good security feature, it woke me up straight away ha

[tiger99]

If you want to isolate the fuel system, you can get a valve which goes in the main fuel line under the floor, with the operating lever typically coming through the floor, out of sight under the seats. That would give you much the same facilities as isolating the fuel pump, but workable with a mechanical pump.

[Jack BRCG]

iv got the switch already and its easy to fit but thanks for the idea

[jimnali]

Years ago I fitted a switch to disable the fuel pump after a similar theft.

It worked great as an anti theft device - just ask the garage mechanic who tried to get it on the ramp for an MOT after I left the car on the forecourt with the pump switched off!