Electrical Where to wire in a kill switch besides fuel pump relay

AnthonyA1234

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#1

• Nov 7, 2024

• #1

I want to wire in a kill switch in my fox for theft prevention. I did a wire tuck so my fuel pump relay is under the fender now so I can’t do the kill switch there like I see everyone recommends. What’s another easy to get to place where I can splice in a kill switch?

 

90trunk

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Mar 5, 1999

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#2

• Nov 7, 2024

• #2

Negative side of ignition coil to ground.

 

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Noobz347

Stangnet Facilities Maint Tech... Er... Janitor

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#3

• Nov 7, 2024

• #3

Clutch Safety Switch

 

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AeroCoupe

lube between the nut and the face. I know my lubes

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#4

• Nov 8, 2024

• #4

Relay behind the rear trim panel that interrupts the inertia switch. You can use a ground to to trigger it and bring the switch up to the front of the car or where ever you want.

Bosch Relay


Put the wire coming to the inertia switch on 30 and 85, 87 would then go on to the inertia switch. 86 would be a switch triggered ground.

 

AnthonyA1234

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#5

• Nov 8, 2024

• #5

Thanks for the suggestions. Now that I think more about it, I could still do the fuel relay kill switch on the red wire. I can just get the wire where it starts, which I believe is at the pcm relay in the passenger kick panel. I’ll cut that wire and splice in a switch there.

 

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AeroCoupe

lube between the nut and the face. I know my lubes

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#6

• Nov 8, 2024

• #6

Just make sure the the current draw on that wire is supported by the switch. I like running everything through relays.

 

AnthonyA1234

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#7

• Nov 8, 2024

• #7

AeroCoupe said:

Just make sure the the current draw on that wire is supported by the switch. I like running everything through relays.

Click to expand...

According to the Jrichker write up he said that wire only gets 1 amp of current so it’s safe to do. Should be good to go

 

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Blown88GT

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#8

• Nov 9, 2024

• #8

AnthonyA1234 said:

According to the Jrichker write up he said that wire only gets 1 amp of current so it’s safe to do. Should be good to go

Click to expand...

The coil side of a relay draws no more than 100-300ma.

 

AnthonyA1234

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#9

• Nov 9, 2024

• #9

So I got to the eec relay. I have two red wires going into the relay. Which should I cut and put the kill switch into? One of the red wires goes down into the computer, the other one goes out and through the firewall to hopefully the fuel pump relay. I’m planning on cutting the one that goes up off the relay towards the fuel pump relay. Can anyone just confirm this for me that this is correct.

 

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Last edited: Nov 9, 2024

AnthonyA1234

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#10

• Nov 9, 2024

• #10

Here’s what I read in my electrical diagram book, it shows that the red wire comes out of the computer, then is at the eec relay, then the fuel pump relay. It’s listed as 361 vehicle power.
If anyone can confirm this is right for the kill switch and I should cut the one coming off the eec relay and heading up towards the firewall I’d appreciate it

 

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AnthonyA1234

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#11

• Nov 9, 2024

• #11

I cut the wire and spliced in the switch where I showed I was in my previous posts and it still starts and runs the same with the switch on or off…

Anyone know what I’m doing wrong here

This is what I did

 

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AnthonyA1234

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#12

• Nov 9, 2024

• #12

I’m looking at this diagram I found of foxbody wiring. i suspected maybe that switch was bad and was stuck on all the time. I disconnected the wire so that the circuit is completely broken and the car ran fine. I don’t understand how my car could still run the same and everything works being as though I cut that red wire….

 

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gkomo

now i can hopefully expect to receive the shaft

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#13

• Nov 10, 2024

• #13

I see you’ve replied to yourself a few times. I just want to say I’m no help, I have no skill when it comes to electrical sh*t, but I am following along to gain some knowledge.

 

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Bullitt347

I have been doing it wrong this whole time

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#14

• Nov 10, 2024

• #14

You could use a momentary switch for the trigger wire to the starter relay.
Engine won't crank unless the momentary switch is held while key is in crank position.
Fed X trucks use a momentary switch to get the transmission out of Park position.
Truck will start and run but the shift lever will not move out of Park without pressing the switch.

 

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