I want to wire in a kill switch in my 87 4Runner and decided to use the Circuit Opening Relay. my question is what wire would I use to splice in the kill switch? I was thinking of E1 as I want to shut it all down. would that be the best choice or .... +B, STA, E1, Fc. or Fp?

 

Why? Is this an anti-theft measure? Do you want to avoid the starter solenoid wire, so that your thief won't know (immediately) there is a kill-switch somewhere?

If you wire the switch into the FC line, the truck will start, but only run for a few seconds and then die. After once or twice of that, your thief might think your truck just doesn't run right, or she might be afraid of attracting attention.

Back in the carburetor days, an engine could run for 30 seconds or more after the (electric) fuel pump stopped. The idea of putting a kill-switch in that circuit was so that the thief could pull the vehicle out onto the road before it died. Then the thief would take off, and you'd (hopefully, but not really likely) get a call from the authorities to come pick up your vehicle.

 

Yes it would be for an Anti-theft tool.

 

Now by this point your vehicle has been entered !!

Easy to Pop the Hood and do interesting things

If your vehicle thief is just after a quick ride and not stealing with a purpose to fill orders for Toyota 4x4`s

I would break the circuit on the ground side of the fuel pump .

For what it is worth you now eliminate just jumping B+ to Fp which any thief having done their research would do it would bypass 95% of all fuel system kill switches

 

So stay away from the starting system and go for fuel pump ground?

 

If you have a really determined thief who wants your truck, he'll just tow it. Your kill switch will mean nothing.

If you have an experienced thief without a tow-truck, he's seen more kill switches than you ever will, and he knows all the usual and unusual places to look for them. I'd be really surprised if any thief would be so determined (and knowledgable) as to pop the hood and start fooling around with the diagnostic plug, but I'm not a thief, so what do I know?

But why would someone with that experience and resources want to steal a 30-year-old vehicle, when right next door is a 2018 Tesla?

So I would think you're concerned about a snatch-and-grab joy-rider (or maybe someone looking for a getaway vehicle). And you just want to discourage him, so he'll move to the next truck. If you put your switch in the starting system, it will be immediately obvious that there is a kill switch. Break the ignition lock, turn it to get nothing, what other explanation could there be? But if you put it in the fuel system, it will crank and crank but nothing will fire. Is it out of gas? Really out of tune? Or is there a kill switch?

But if you put your switch in the FC circuit, it will turn over and start -- only to die in a few seconds. What kind of kill switch would do that? Time to move on.

Your choice. Just don't post here where you put the switch. ;^)

 

My home has "mean" dogs, security lights, and fence and security gate, not worried at all about things at home. I am more concerned with just going out to the store or whatever so doubt much planning would be involved if it was a target so more of joyride thing I am thinking. 50% of the time I have 2 Bull Terriers and a really mean Corgi heh in the back, but the other times I just am a bit worried. I have seen 2 4Runners (1st Gens) and 1 Pickup(2nd Gens) stole from the area in the past 7-8 months.
I am pretty good with hiding wiring and such as I like to up-cycle vintage things to make them look old but have new upgraded components. I also designed a DPDT latching relay I can use for it, so it shuts off without me doing anything but turning the ignition off. So just need to turn power on to push the momentary switch.

 

Cool.

Use the glove-box-light switch as your momentary. Truck won't run unless the glove box is opened after you turn the key. Then there won't even BE a kill switch to look for!

 

Must be rough living in a place like that my Keys pretty much stay in the ignition unless the buzzer is giving me a Headache

 

Not sure that is a good idea, if the person stealing the truck opened the Glove box.... vroom..I did think it would be funny to use the horn button as one though.. what person stealing a rig would want to bring attention to themselves honking the horn? I have a much better idea in mind and will be almost impossible to find. I would just rather not say what my switch will be.

 

I use to back in the day myself, but a lot of tweakers here now.

 

Hello,

I read about your advice for a kill switch to the FC line on the curcuit opening relay on the 4runner. I have a 91 4runner 5spd 3vze engine and am looking forward to try making a kill switch either like you said or to the fuel pump (cranking but no start).The thing is I havent done anything like that yet and sadly I am beginner at the electrical stuff.Can you give more info on the process? So far I think I can locate the relay itself - should be behind the glove box, maybe behind the speaker on the right side of the glovebox.

Thanks in advance!

 

If "put a switch in the FC line" is currently a mystery to you, this might not be the right place to start. Not because it's electrically complex (it's not), but because you don't have much room to install splices. And if you mess them up, you could get stranded.

But everyone has to start somewhere. Find the the COR (you have the drawing above). The FC line is probably G-Y (fuel pump line is probably L - solid blue). But you're not going to guess. Unplug the connector from the relay, and with your multimeter (don't have a meter yet? No excuse for that! https://www.harborfreight.com/7-func...ter-63604.html) check for continuity to ground on the wire you think is FC. It should be open; move the vane in the VAF and you should get continuity to ground then.

Then you just cut the FC wire, and splice a SPST (single-pole, single-throw, generic switch) switch into the circuit. When the switch is closed, it works normally. Open, the truck will start, but die in a few seconds. Instead of trying to hide the switch, I'd suggest getting a real automotive switch like https://www.aliexpress.com/item/Aude...27424c4djbWQw9 and snap it into your panel. Hiding in plain sight!

NakedRunner's idea of using a DPDT relay (wired to make it "latching") is very clever; the starting circuit is disabled whenever you turn off the truck, without you having to remember to throw a switch. But it makes it next to impossible to use Valet Parking!