Kill switch for 88-95 Honda Civic/CRX/DelSol
 

*thought it was about time to drag this over from GS*

So I just installed a kill switch in my CX and I thought I'd share the info with all my fellow Civic owners so that you will not have to obsess over wiring diagrams all afternoon like I did.

This How-To (for the "basic" kill switch) will work for all 5th generation Honda Civics and DelSols (1992-1995) that have airbags (SRS).
Difficulty level **
Advantages: fast engine kill, easily removable (you'll never know it was there).
Disadvantages: also kills the speedometer/odometer while the switch is off.

First, let's list the parts that you will need:
-Inline ATC style fuse holder
-Interrupter switch (simple rocker switch sold at an auto parts store)
-Male spade connectors (2)
-Female spade connectors (2-3)
-Butt Splice connector (1)
-Round or forked terminal (optional)
-5' of 16-14awg wire
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First I'd recommend you find some place that you'd like to put your switch in. The easiest thing to do is to find a blank accessory panel in your dash and install the switch in there. Just gently pry one out with a small screwdriver.
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Next you need to open the fuse panel under the dash, and locate the 15 amp fuse that supplies the switched power to the PGM-FI main relay. Pull out this fuse. Now try to start your car. If it cranks but won't start, you pulled the right fuse. Congrats.
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Now you have to put together the wires that will run between the fuse box and the switch.

-The first piece will be about 2' piece of wire with a male spade on one end and a female spade on the other. (shown at top of photo)

-The second piece will start with the ATC fuse holder, but a male spade on one end, and the butt splice on the other. The butt splice will connect to one end of an approximately 1' length of wire (depending on where your switch is placed), with a female spade on the other end. (shown in middle of photo)

-The third piece is optional and only applies if you have a lighted switch, a lighted switch requires a ground wire, so you need a piece of wire about 2' long with a female spade on one end and a round or forked terminal on the other. (shown at bottom of photo, coiled)
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Now you'll need to cut a hole to mount your switch in.
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Now put your wires through the hole you've made, and hook them up to the switch the first wire will go to the terminal marked "switched" (or something like that, markings will vary among manufacturers)
The second wire (with the fuse) will go on the terminal marked "power"
and the final ground wire will go on the terminal marked "ground" (if you have one)
http://i239.photobucket.com/albums/f...r/IMG_4823.jpg



Now, put that 15 amp fuse that you pulled out of your fuse block into the inline fuse holder in the second wire. Now plug in the two male spades in the first and second wires into the place in the fuse block where the 15 amp fuse came from. If you have a ground wire, just find a bolt or screw that goes into a metal panel or firewall, loosen it, and slide the terminal of the ground wire underneath. Re-tighten the bolt and you're done. http://i239.photobucket.com/albums/f...r/IMG_4825.jpg



Enjoy your kill switch!
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Nice! I don't think I ever saw this, :)

The "Advanced" kill switch will work for any 88-95 Civic/CRX/DelSol.
Difficulty level ***

Advantages: speedometer/odometer function, works on more cars.

Disadvantages: takes longer to kill the engine (startup is still very quick though).
This version is only slightly more difficult than the "basic" switch.
It does not have the instantaneous "kill" of the basic switch, but the speedometer/odometer is unaffected.

Parts List:
-Interruptor Switch
-Two lengths (about 2') of 16-14awg wire
-Female spade connectors (4)
-Male spade connectors (2)
-Heat shrink tubing (preferred) or electrical tape.

Mounting the switch remains the same. The only difference is in the wiring under the dash.
This time we will begin by prying up the drivers side scuff plate.
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Now look just under the carpet, there should be a long skinny black plastic conduit box. If you pry open the conduit you should see a plethora of multi-colored wires.
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If you have a 92-95 Civic you'll be looking for the only yellow wire with a green stripe on it, it should also have small silver dots. This wire will henceforth be known as the fuel pump wire For all of you 88-91 Civic folks, you're looking for the yellow wire with a black stripe (may also have dots) This too will henceforth be known as the fuel pump wire Separate the fuel pump wire from the rest and cut it about 1/3 of the way from the front (firewall) side of the conduit.
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Now you'll need to put a female spade connector on one end of the fuel pump wire (seen above) and a male spade connector on the other end of the fuel pump wire (seen below)
http://i239.photobucket.com/albums/f...r/IMG_4859.jpg


In preparing the wires that run to the switch, attach a female spade connector to one end of both wires, attach these connectors to your switch. On the other end of the wires, attach a male spade connector to one, and a female spade connector to the other.
http://i239.photobucket.com/albums/f...r/IMG_4860.jpg



Attach the switch wire with the male connector to the female connector of the fuel pump wire, and the female connector of the switch wire to the male end of the fuel pump wire. I highly suggest that you cover all of the exposed metal of the connectors with electrical tape or preferably heat shrink tubing. This will prevent the connector from accidentally shorting out your fuel pump.
http://i239.photobucket.com/albums/f...r/IMG_4862.jpg

I also found a kill switch mod on Instructables.

Seems pretty straight-forward.

I was thinking both a start and kill button on my stick shifter would be pretty cool.

Has someone done a kill switch for a Gen 6 Civic, that is, '96 - '00?

I like the "Advanced" switch better--not only because it keeps the odo running, but killing the PGM-FI means killing the computer, and that's an expensive bit to switch on and off a dozen times a day.

Check the wiring on your main relay... I can't remember the pinouts right now, but you can put a switch on one of the pins to ground it, and it will shut down the fuel pump.

You could also put a switch inline with your ignition system, which will instantly kill the engine without killing the speedo and odo.

You can also interrupt the power supply to the fuel injectors, which is what I plan to do. Eventually...

-soD

Whatever happens, I prefer to also cut the power to the coil/ignition system. I've been told that since the coil/ignitor setup is essentially a capacitor, that it shouldn't be left with power when it's not discharging.

I don't know if it's true or not, I never bothered to research it, because it happens to fit into my cutoff switch plan anyway, but every time I've made a cutoff switch for anything, that has been the primary thought.

Other than that, I don't like cutting fuel first, as this can put you in a lean situation (especially a fuel-cut rev limiter).

And if you cut ignition first, without cutting the fuel pump, you're still pumping fuel through the engine until it stops... so you're flooding the engine, putting fuel into your oil, and polluting that much more... which is why I decided to make a fuel/ignition cutoff instead of one or the other...

I'm thinking it would be easier to cut my injectors though, since they share a common signal with a switched (at the ECU) ground.

I could put the switch on the signal... but as soon as I hit it, I'd end up with a code 16 in my ECU (Injector(s)) That wouldn't reset unless I put a ECU reset switch in my car... (My car's reset procedure is "pull the hazard fuse" but you can just switch it so that it grounds momentarily)

Interesting. Does doing an 'ECU reset' actually disconnect and reconnect power, or does it signal the ECU to do a warmboot? I don't have a camshaft sensor in my Accord, so ideally I'd like to disable the injectors, but I'm trying to avoid powering the ECU on and off, since it's one of the more expensive bits in the car to replace.

In my car, you can pull the hazard fuse and still start the car, and drive it around. It's just that 2 things happen:

1. You won't be able to use your Hazard lights... (duh, you pulled the fuse)
2. The CEL will light up while the ignition is on, but as soon as you shut it off, it will clear the code.

Pulling the hazard fuse essentially allows the ECU to delete it's running memory (when powered down) and re-upload the memory (on next power up) from the solid-state program (the one that never changes) in the ROM. It will not prevent the ECU from actually throwing a code though.

Switching the hazard fuse in my car is a quick way to reset it while tuning.. every time you do something to the car, it's a pretty good idea to reset it... as with any other ECU controlled vehicle.

A couple of seconds of lean operation isn't enough to damage the engine, IMHO. It takes significantly more than that to heat up the pistons/chambers enough to really matter, and if you're using it as a kill mechanism the engine will stop running and stop heating up very quickly.

I prefer the idea of cutting the injector power because once you do, the only fuel going in is whatever is already in the manifold--so you'll only get a couple of revs more with any fuel at all, really.

My "other car" has a spark-cut rev limiter, and if you ride the limiter you can load up the exhaust with fuel and then ignite it in the header. Thank heaven for low-restriction mufflers....

-soD

We (friends and I) used to intentionally cut spark to engines while they were at high RPM/load, then cut the spark back on at full throttle as they were about to stall...

think: flame thrower kit.

i've had a look if i could addapt this to my car.

i've been looking over my fuses and found a fuse labeled 'FI' when i pull it the starter will turn but the car won't start, if i pull it when it's running it'll run for a second and than dies.... al electric systems and lights keep running as mormal
reinsert the fuse, nothing happenes, and it can start as normal....

sounds like this is the fuelpump and yes, somewhere on the web i found this fuse is for:

Fuel pump
Control unit
anti-theft warning system
Immobiliser (radio controlled)


i have an alarm but no immobiliser so i don't have to worry about that, but what about the controle unit part? other fuses are also labeled "Control unit" amonst other things according to the same source so what does this stand for? as everything else keeps running as well i don't think it cuts out the ecu

would there be a downside to basically wireing a switch in series with this relay to act as a stop switch?
as opel is GM perhaps american early 90's GM car use the same layout

if it does just interrupt the fuelpump that might be my best bet for a simple safe start-stop switch... my only problem with interrupting the fuel pump is that it might prevent smooth (bump) restarts
however i would not have to cut any factory wires so the system could be fully non intruseive... there does not seem to be a fuse for the injectors i can find, sofar an injector cutoff is not an easy option.

control unit might have something to do with an ECM, if you have one. You'd have to get a FSM and trace the fuse location.

An injector cut off is not an easy option, by any means. It happens to work fastest though. Cutting the fuel pump is an OK way to do it, but you should not (from what I've been told) leave the ignition system on, as it could cause damage, according to some FSM's and techs alike.

i'm not sure im with you here, i mean i can see it's not a ideal situation where the sparks keep fireing when there's no fuel going to the engine as they might be cooled by the fuel.
but how exactly whould leaving the iginion on be bad?

if i where to cut out the fuelpump i'd press down the clutch, pop it in neutral and while doing that, cut out the pump long enough to starve the engine...
than i'd eoc on, and when it's time to restart the engine depending on the speed, either start with the electric starter possibly with a start switch next to the stop swith, or bumpstart
(which could be a problem as i imagine there's no fuel going to the engine immediately...)

so only when the engine was "starveing" it would be running for a second or so with little or no fuel in it... but than it would stop turning and the spark plugs would stop fireing... this situation would be fairly identical to switching the ignition to on, prior to starting the engine no? or would the ecu interpred things different and perhaps keep fireing the spark plug of the cilinder that was about the enter it's power stroke?...

what's an ECM? en electronic controle module? but for what?... could this be some sort of fuel pump feedback for the ecu perhaps, a simple on off thing that telld the ecu the pumps running or not? it might make sence to give it the same fuese so that when that fuse goes the feeback goes too and the ecu know there's something wrong?

i have the wireing diagrams for the car, but they're a little over my head... i night be able to isolate the fuse though and see what it's connected to...

I think it would be okay. Some vehicles require special handholding to run with a sparkplug removed (i.e. the spark plug needs to be grounded to the body or whatever), but I don't think that matters if everything is installed and firing as normal. The only issue I could see is that the fuel injectors and fuel rail are cooled by the fuel, so you could get some overheating, but for the two or three minutes, max, that you would have no fuel flowing, I imagine it would be okay.

I wouldn't switch off the ECU if possible; I doubt it's designed to handle being switched on and off dozens of times a day, and it's one of the most expensive bits in the car. Somebody mentioned interrupting the camshaft sensor in OBD2 cars; if yours is so equipped, you might try that. That interrupts both fuel and spark.

i don't think the ecu cuts out as all the dash lights seem to respond normal and the car attempts to start...

i've discovered another interesting thing... i knew my car had deceleration injector cutoff but now i foud the ecu pin layout one pin 50 has this description

TC input signal, ignition injection cutoff

if this is a on/off signal perhaps i could have the ecu cut out the ejectors factory style.... that would be pretty cool

leaving the ignition system powered on without a way to discharge is harmful to your ignition system... your ignition coil is essentially a 12v->30-60kV capacitor <(--- what I meant by that.

Again, I don't know if it's damaging or not, but I dont do it either.

The '93 lumina is OBD-1 still, so no go on the cam sensor, I'm pretty sure.

If you have a COP ignition system, you can cut the power to the signal wire for the crank trigger. (Coil on plug, coil per plug) There will be a sensor on your crank somewhere that has magnets on it.. it will also have a signal and circuit wire, you can interrupt that signal to cut spark.

Do not confuse this with the CKP (Crank position sensor) as the CKP isn't necessary to run the car, just to make it run correctly.

Kill swicht, auto re-start, mild hybrid:
 

Hello everyone, I've been reading this post since and recently made my first kill switch for EOC mode. I have a 1998 Suzuki Swift 4 cylinder with manual transmission.

The parts I used:
5 contact relay, Single Pole, Double Throw or SPDT (40 amps)
Relay receptacle
Momentary push button switch (normally open)
Wire/Cable
Soldering Gun
Insulating tape

I used the SPDT relay, the 30 and 87a terminals to interrupt the current flowing to the positive side of both coil packs, since my engine has 2 coil pack, but with a common positive wire.

The terminal 85 was connected to the positive side of the ignition, but source, not the coil side, but the rest of the harness side.

Terminal 86 was connected to ground via the momentary push button switch. So I only had to lead one wire through the grommet of the fire wall and in to the cabin. And its ground, so in any case of a wire scuffing, the worst case scenario, it will not catch fire, it will only turn off the engine.

When I want to kill the engine, I throw it to neutral, then I push the button until engine looses all the RPM's. Since it's a momentary switch, ass soon I release it, it will be ready to start with the starter or with the inertia of the car and it's manual transmission.

The fuel pump will deactivate after about 5 seconds of no RPM detection. Also, there is no fuel injector, nor any ignition coil activity since there is no RPM detected. Everything is stand by for the next RPM movement. Still in test mode, but it's working fine. My scanguage remain on, so I don't loose the current trip memory.

The next thing I want to do is to make a circuit that automatically re-starts the engine when I press down the clutch down. But only if the engine is off. I can to this with an Op-Amp comparator and the Charging light. Since the light goes off when alternator is charging, and alternator start charging about the same time engine is on steady. I will be doing this in the near future, and will keep you informed.

Another idea is to use a hybrid alternator, those used on GM's Chevrolet Malibu and Saturn Aura engines. They use an Ecotec 2.4 L and they start the engine with a belt driven alternator/starter (BAS). If I find one of those, I could even make my car a mild hybrid, better than the pathetic 24/32 MPG those Malibu's and Saturn's currently achieve, since I will be using a much smaller 1.3 L engine. What do you people think about this idea. Would it be feasible?

old post but thanks was planning to do a kill switch on my 95 civic

I just finished installing the basic kill-switch. It is cool that the engine dies instantly but do not like the fact that the odo/speedo dies as well. Gonna change the wiring today to accomodate the advanced setup

Has anyone done the kill switch mod as an ignition kill only? :confused: If you have, and been living with it for a period of time, please let me hear from you.

From reading all of this, I'm still unsure about killing just the ignition. My rational behind wanting to kill just the ignition, is it's on a relatively small (fuse capacity) circuit and located conveniently behind the left side of the dash. The fuel pump is on a circuit with a very large fuse located in the engine compartment. The manual says its CB box is a watertight box. As the car came with a 100,000 mile warranty, I believe that the mod would be obvious if done to the fuel pump circuit and would likely have an adverse affect if a warranty issue arose. :eek:

You could make something worth a solenoid valve and the existing fuel lines that bolts in, that way it's removable.

I'm confused as to what kill switch to place in my car :/ .. Any help?

Edit: I mean, in which way should I do it? The first or second guide? Or neither?

You know, it occurs to me that, unmarked and left in the off position when you park your car, kill switches could be a great anti-theft device since so few car thieves will ever have encountered them, know how to use them, know how they are wired. DIY is power!

Some insurance companies consider it an passive security device, resulting in additional discounts.

Easiest for you is an injector kill. There is a single power wire that feeds a resistor box, it's the only wire on the box that is a different color. The box is a finned aluminum case mounted on the drivers strut tower.

Switch inline with the different colored wire will kill power to all four injectors. This assumes you mean the CRX.

Sweet! My mother works at allstate:) I'll have to talkwith her about that one!

Well thatmay be the easiest but is it the best??.. And yes I mean my CRX

I want to do the kill switch tonight. Is this the best way to do it?

--Easiest for you is an injector kill. There is a single power wire that feeds a resistor box, it's the only wire on the box that is a different color. The box is a finned aluminum case mounted on the drivers strut tower.

Switch inline with the different colored wire will kill power to all four injectors. This assumes you mean the CRX.--

Thanks for the help..

And what gauge of wire would I need for the Kill switch Christ suggested? 14 Gauge still?

For 15 amp fuse you can use 18 guage, for a 20 amp you need 16, for a 25 and 30 you need 14 gauge wiring.

Why can't you just kill the engine with the key and then turn it back to the on position, while in neutral, to power the odometer?

Two reasons:

1. I don't feel comfortable power-cycling the ECU that often.

2. I have a few long hills that require engine braking, but I don't think my engine is new enough to have DFCO, so I'm always burning a little fuel, even downhill with the throttle closed.

You can simply turn the key off and then back on and it will restore power to the speedometer and odometer. That method absolutely works.

You'd need to be very careful to not lock the steering column on most cars. Additionally, besides the stress on the electronics that could shorten their life, you will wear out the ignition switch sooner.

You may have heard the saying, "You pays your money and you takes your chances." It applies here as well.

My 1990 CRX does have DFCO, according to the owner's manual. Sadly, it ceases cut-off when the revs drop below about 2500 RPM, I think the number was. An RPM which my engine rarely goes above in any circumstances.

Your Accord may be similar; it may have DFCO which isn't useful the way that we tend to drive.

-soD

I just did the fuel injector cutoff on my 1995 civic vx. way easier than I would have even thought. I used the extra accessory spot next to the rear defroster as that is closest to what I am used to using when I was just doing the key turn off method of E.O.C. . The ability to use the right hand which is already in the process of shifting into neutral as opposed to having the switch control of the steering wheel seemed more safe and accessible to me. the only problem I have had was once when I didnt switch the switch all the way back, I was on the freeway and was a bit worried, had to get to the side and stop to figure it out. stopped using it for a while then used it again in my normal safer conditions and found out the problem! Thanks Andrew fro the write up, I know you prob dont check this any more as you sold the rig a while back but thanks anyway!

i have 1988 civic and all i do is turn the key back one click, engine turns off, steering wheel stays unlocked, head lights work but blinkers dont, i have installed a engine start switch. key must be turn forword to the run, the key will not start the car anymore. i've been doing this for two years now with no problems so fare and brakeing with out power not that hard its like the none power brake systems of the old days just press harder, if you are to week just turn the key for the power.

OK I am doing the engine kill switch, I don't think I will use the clutch pedal to kill the engine as sometimes when I come to a stop I need the clutch pedal...


So i've decided to mount a switch on my shifter knob.

Now, for killing the engine, I was going to use the injection system, but since I have a fuel vaporizer system on my PCV system, the engine will still be getting a fuel source and possibly running. So, I would like to use the camshaft position sensor. The Fuel pump sounds like it might give a delay to my kill / restarting operation.


my Car is 1993 Honda Civic Si, and I've only found a Crank position sensor which is inside of the distributor, according to autozone, and the USDM.


I am not sure if this would do the same thing,. I don't want to damage the engine. Is it ok to open this circuit ?? And, should I Momentarily open this circuit using a Momentary switch (and a relay), or do I need to keep it open using a non-momentary switch ?


Thanks I will be waiting for some answers.