How to (reversibly) disable the truck?

[Yarek]

Hi guys,

Please have mercy on me: I'm just a bit challenged when it comes to electrical stuff and I'm hoping someone can help me without too much judgement.

Here's the story: where I live, truck theft is rampant now. I felt like I was safe because my truck is about to turn 21 this summer, but nope: vehicles just as old are getting stolen from the streets now. Mine is tucked away in a very narrow driveway and so it's not as visible from the street, but I'm afraid someone will come for it one of these nights.

I'm thinking about installing a kill switch in some hidden location, but I have a hard time identifying the fuel pump relay and the proper wire to splice. Maybe someone can help me with that? if you PM me, maybe we can get on FaceTime or something like that? I can definitely take it from there.

In the meantime, I'm thinking I can just pull out one or more of the relays that are in the cabin. I don't drive the truck every day and so it won't be too much of a nuisance to pull it out, and put it back in when I need to go somewhere. What I'm afraid of, is that I'll pull out the "wrong" relay, and I won't be able to lock/unlock the truck, or that some stupid computer somewhere will lose its programming, or some other apocalypse will happen. I understand simple electrical circuits, but once black boxes are involved, I'm a bit lost.

If someone can help me with this, I'll be very much obliged. The truck is just like my description says: 2001 (built in 2000) Ram 2500, V10.

Thx a lot guys and gals!

 

[pacofortacos]

I don't know of any relays in the cab, but under the hood there are a couple of relays. Fuel pump and ASD relays.

I have the manual for a 2001 Dakota, and I don't know if the wiring is the same on the 2500 and Dakota.
But Terminals 85 and 86 on the fuel pump relay are the 2 wires to the coil side of the relay. 86 is the 12 volt side that on my diagram looks like it comes from a 10 A fuse (fuse 10) from the inside fuse box (I think).

That fuse also goes to a few other things.

My diagram shows - on the ignition switch, pin 3 ( it should be a Dark Blue wire) goes from the ignition switch to the fuse that feeds the fuel pump relay.
IF your ignition switch wiring looks like that, you may be able to put a switch on that wire.

To be honest, the simplest thing to do is to just pull the ASD or fuel pump relays from under the hood.

Or if you can find the wiring diagram for your truck, it would be easy to figure out.

Dodge used to be pretty good at keeping a lot of wiring locations standard across many lines and models.

 

[SYKRAMMAN]

Like said above, the asd relay is easiest and quickest way to disable the truck, it will crank but not fire, keep a good pair of pliers in the truck, the relay is a pita to get out sometimes.

 

[Yarek]

These are the pictures I just took. The first one is the little bundle of cables etc. under the dash that I was referring to. I remember being able to take that thing off before, but it didn't come off today. I think I remember seeing some video somewhere, that said that the white connector with a black latch, has the right wire to splice to put a killswitch in place, but I couldn't identify which one that is, because a few of them turn from cold to hot as the ignition switch goes on.

Anyways, the pics of the relay box are here too. I realized, that the small relays are all the same (7 of them), and the larger ones are also the same (3 of them). Assuming that the prospective thief is a bit smarter with electrical circuits than I am, I guess I will need to pull out all 3 larger relays to make sure they don't just move one over? or would pulling any single one disable the truck?

 

[PolarisCobra]

I suspect you could just pull the starter relay and call it good. If they get into the truck, and try to jumpstart it, and it doesn't start, they will likely just move on. Not likely to take the time to pull out a flashlight, find the fuse box, and figure out which relay to move.

If the crooks were that smart, they would probably have a job in the first place...

 

[WY-Dave]

A old trick I used to do is find a lead off the ignition switch and extend the leads to the disconnected cig lighter socket. When you push in the lighter to normally get it hot, the ciglighter completes the circuit. Then when I wanted to disable it, I would pull the light out. BUT you have to modify the cig lighter by taking out the coil. I just had a friend throw in some weld and ground it flat. For extra security, you can take the lighter and put it in your pocket/night stand/shelf etc.

Also setup a friends car that to start it, it was tapped off the parking break.

 

[Matt Bell]

If you wanted to do a kill switch I’d just run it off your ignition wire to starter relay. It’s very open in the engine compartment, easy to run wiring wherever you want it.