Kill switch how-to

[steffen707]

Originally Posted by lsemple

OK thanks, I know which relay it is I was playing with it the other day. I just mis-understood your question.



ok so this is my goal.

going to get a 12V 2pST relay, and a 2P2T rocker switch (on-off-on),



I will be putting the relay on the clutch pedal switch and connecting it to 12V accessories power, so when the clutch is depressed the relay is deactivated (the clutch pedal switch is a normally ON switch <normally closed>).


the 2p2t rocker switch will turn my engine-cut-off circuit On or Off, or Disabled.


when the circuit is DISABLED, the clutch pedal switch resumes normal operation via the one of the poles on the relay (prevents car from starting when in gear), and the Engine Kill circuit is shorted out.

when the circuit is OFF (center position of switch), nothing works (anti-theft device),

when the circuit is ON, the other pole on the relay (relay is activated by the clutch pedal), will cut power to the MAIN RELAY which will kill the engine !.


So driving down the road, I can press the clutch pedal all the way down and it will kill the engine, I can start it by releasing the clutch pedal.

I can drive normally by not pushing the clutch all the way in.


I might have another momentary push button bypass switch also which can allow me to flip the toggle switch from ON to Disabled without killing the engine OR use the clutch pedal without killing the engine. This push button will be on my shifter knob.


EMAIL ME if you would like this circuit diagram, I think I have it mastered.

THought I would share my thoughts

2 things to consider.

You need to push the clutch almost all the way down to start the car, as it has a clutch safety switch so you don't start the car in gear. Your setup may make the car unstartable from a stop unless you disable the new clutch engine kill switch with your rocker switch.

I would look into the normally closed push button swith and mount it to the shifter, it is so stinking easy to shut the car off now. Your feet are already busy with 3 pedals and your right hand can shift and shut the engine off while the left hand steers.

I know it sounds nice to use your clutch foot to shut the engine off, but I prefer the button on the shifter.

[lsemple]

"You need to push the clutch almost all the way down to start the car, as it has a clutch safety switch so you don't start the car in gear. Your setup may make the car unstartable from a stop unless you disable the new clutch engine kill switch with your rocker switch."

An integral part of the circuit will be that when the circuit is "on" the system that prevents the car from starting in gear will be bypassed (car will be able to start in gear).

It will be restored when the engine kill system is set to the "disabled" position. (2nd on position of toggle switch)

when the engine kill system is set to "OFF" (center position of the on-off-on sw.) nothing will work, car wont start ect. and it will be a theft prevention device then.



"I know it sounds nice to use your clutch foot to shut the engine off, but I prefer the button on the shifter.[/QUOTE]"


well I am going to try it :S.. and I will let you know soon how I like it.

if I don't I've already made up a gear shifter with a normally closed push button on it.

good thing is I am incorporating the toggle switch to change the entire setup so everything is back to normal.

but to start the car when my system is on, I will have to either keep it in neutral, or keep the clutch pressed 3/4 of the way down so the Main Relay doesn't get shut off.

I almost want to put an LED on the system so I know when the clutch button is being pressed.


lots of ideas here. when I am done I will report my progress.

[lsemple]

OK new Idea;


deleting the 2p2t switch which allows me to enable or disable my clutch-engine-kill system.

Instead I am going to use a relay, with 2 N/O and N/C contacts. (DPDT relay)


when the car engine is running, the relay tells the clutch pedal switch to be used as an engine kill mechanism.

when the car engine is not running, the relay tells the clutch pedal switch to prevent the engine from starting unless the clutch is pressed.


simple.


now when the car engine is off I can re-start it easily, incase I get stuck at a light and accidently press the clutch all the way down.

I wonder if there would be a way to detect if the car is at a stop [not rolling] or not, I could use this to make it so that if this is the case, then my circuit would also be off, which means that the relay tells the clutch pedal switch to prevent the engine from starting unless the clutch is pressed. (back to normal).



So the only time the clutch pedal swithc works as a engine kill is A) when the car is rolling AND B) when the car engine is running. If either of those two events happen then the clutch pedal switch will return back to normal operation.

Thoughts ?

[lsemple]

disadvantage of kill switch on shifter knob,
------------------------------------------------


- easy to knock / hit, accidently push. which might bad considering your foot might not be pressing the clutch pedal and the car will be in gear when you are killing it unless you added a 2 or more pole relay to your clutch pedal switch so you get more "switches" out of the one switch, allowing you to prevent the engine from being killed unless clutch pedal is down.

- trying to retro-fit a push button inside of a shifter knob is tricky, and shifter knobs with push buttons already on them can be pricey.


advantage of the kill switch on the shifter knob
-----------------------------------------------------

- easy wiring.







Disadvantages of CLUTCH pedal switch.
----------------------------------------

- you are disabling a major safety feature of the vehicle which is preveting it from being started in gear. This is a safety issue and so there fore you should take measures to work around this. like have a sensor that detects if the car is in Neutral so the car won't start if its in gear.

- it is impossible to use the clutch as both the engine kill switch AND a switch that is used when you are starting the engine. How can you start an engine when its Main Relay is disabled ? You have to find a different system. The Neutral position sensor on your manual shifter knob is one way (if you can make it somehow).

- when driving you cannot press the clutch pedal completely if you are trying to accellerate strongly. But if you are good at the clutch or have a good clutch pedal, or adjust the clutch pedal, you can still complete a successful shift even if you don't press the clutch fully down.- but slower driving = saving gas..




advantage of the clutch pedal switch.
-----------------------------------------

- your gears will not be engaged if you accidently kill the car because your clutch is disengaged.

- easier to use more frequently your clutch is pressed quite a few times in one trip--> save more gas; you would have to get very skilled at your new layout for your pedals. I've been practicing my half clutch gear changes and stop signs lately.

- causes you to drive slower so you don't kill the engine (driving slower = saves more gas Feathering the clutch pedal foot all the time will probably cause you to also feather your driving foot on the gas pedal (subconciosuly).






Anyone know how to make an automatic engine re-start circuit ?

[Quezacotl]

Hm, if i can't find the camshaft sensor, or it does'nt work, then what should i cut?
Injection and ignition, or just injection?

[Quezacotl]

I have'nt done anything yet, been busy. But i have been thinking about doing this EOC to work automatically.

What are your thoughts for this?

-Get VSS throught Hz-to-V converter(LM2917?)
-Get VSS throught comparator(with hysteresis)
-Interrupt switch between comparator and FET(gas pedal)
-Output to FET that switches camsensor.

I thought that would be the best circuit for this, as it would keep the RPM at engine idle if speed drops enough, and when you press the gas pedal, it does nothing.
And of course whole circuit can be switched off

[VXmpgRacer]

I thought I would share my gear shifter mounted kill/start switch. The switch is for a winch and I set it up to kill the engine.
Push down to kill the engine
Push up to start the engine



EDIT: LINKS ********************
Here is a similar model:
http://www.promarkoffroad.com/winch-...t-winches.html

Here is the exact model:
https://amzn.to/2RFdSif

Here's a momentary rocker switch from Granger that would work:
http://www.grainger.com/Grainger/POW...ND6?Pid=search

[lsemple]

Nice job,

looks like you have the same car as I do

[lsemple]

This setup uses relays for the existing clutch podal buttons. The clutch pedal has two buttons, one is for the cruise control release, the other is for preventing the car from starting up when it is in gear. I put both buttons on double-pole relays, then I put the start-up circuit on the same button as the cruise control release circuit, then used the now spare button (when clutch is fully depressed which used to be for preventing engine start if in gear), to kill the engine.

Now when I am driving, if my circuit is turned on via the button on the front of the control box I made, I can simply press the clutch to the floor, and the engine will die. after it dies I put the car in neutral and release the clutch and coast for as long as possible. To start it back up I simply press the clutch again, put it in gear, and then release the clutch pedal (same as push starting the car when your battery dies), the rolling motion of the car starts the car when it goes into gear.

It kills the engine by opening the circuit to the main relay of the vehicle. I found a 15 Amp fuse in the fuse box which says ECM (I believe), which seems to kill the car if removed. I simply took 1/4 inch spade connectors, trimmed them a little, and they slide right into the slots where the fuse belongs. then I ran that to a 30Amp relay (all I had), which opens the circuit when the clutch pedal button is pressed.




This momentary button disables my clutch pedal engine kill circuit. Now I can push the clutch to the floor without having to worry about the engine dying. This is useful when in stop and go traffic.






The button on the front is for turning off my clutch pedal circuit all together, same as button above, but not a momentary button.

[lsemple]

Man this is nice,

unless I have the red button on my shifter knob pressed down, my car will die when I press the clutch down.

I've been coasting all over town like this.

After the car dies I have to turn back on the Main Relay for the car again by releasing the clutch pedal or pushing the red button, otherwise the odometer will stay turned off with the rest of the ECU stuff. This is because I put my circuit in series with the "ACG (s)" fuse in the fuse box which kills the main relay the engine (and the ECU).

To re-start the car I can either using the rolling momentum of the car to "push start" the car by letting go of the clutch pedal when the car is rolling and it is in gear, I use a higher gear to do this like 3rd or 4th most of the time. OR if I am stopped, I just simply put the car in neutral and press the clutch down 1/2 way and use the key to start the car, if I have the clutch pedal fully pushed down the ECU will be turned off by the button on the clutch pedal (good security system

I have to push the clutch half way because I moved the wires from the existing vehicles safety system.... (where the car will not start unless clutch is pressed) over to a second button on the clutch pedal which is used for shutting off the cruise control the moment the clutch is pressed (this button is normally closed, unlike the first clutch pedal button). And so the car wont start unless the clutch is slightly pushed down (1/2 way), and it won't start if the clutch is fully pushed down (because of my circuit killing the ECU (main relay)).

I've used The two cluch pedal buttons as trigger circiuts for 12V double pole relays (one relay for each button), so I can put more than one circuit per button because the relays are double pole. So one clutch pedal button can activate / deactivate 2 seperate circuits using the normally open/closed terminals found on the relays. The vehicle safety system for preventing engine start unless the clutch is fully pushed down is now on the same button as the cruise control disable button).

The relay for the clutch pedal button when the clutch is fully pressed down (this button is now used ONLY for my engine-kill circuit) is controlled by 3 Conditions. The clutch pedal button itself engages the relay, but if the the red on/off button on the front of my box housing the relays is off, or the red momentary push button on the shifter knob is pressed, the clutch pedal will not do anything. The on/off button opens the circuit, and the red momentary push button on my shifter knob opens the circuit, as it is a normally-closed momentary push-button.

So when I push the red button on my shifter knob, the clutch pedal engine kill mechanism will not work. This allows my to drive normally again in tight places (backing up, starting off, going uphill ect ect)..

or I can be driving on a slight decline and simply push the clutch down put the car in neutral, release the clutch, and the engine will have died, and the ECU will have been re-started after I release the clutch pedal and car is in neutral. This way I can be keeping track of my New mileage !!!!


WORKS LIKE A CHARM !


takes a bit of getting used to but this is really not very difficult,

For people with Honda's (I have a 93 honda civic Si hatchback), I can show you exactly which fuse I tapped into (using spade connectors in the fuse slots, and an inline fuse holder for the new location of the fuse).


see my previoius post for advantages / disadvantages of kill button on shifter knob vs kill button on clutch pedal.