ignition kill relay

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=102702
Printed Date: May 05, 2025 at 7:43 AM

Topic: ignition kill relay

Posted By: boostaddict
Subject: ignition kill relay
Date Posted: March 02, 2008 at 5:42 AM

I need a little help. I'm trying to do the exact opposite of this picture here.
posted_image

I need to wire up the relay say that I can START my car when the switch is GROUNDED. When it's not GROUNDED, my car WILL NOT start. I've looked all over for different wiring diagrams and found some, but I'm not sure if they're right for what I'm looking for. If anyone can help me, that'd be really great and I'd really appreciate it. Thanks alot

Replies:

Posted By: i am an idiot
Date Posted: March 02, 2008 at 6:42 AM

Remove the wire from 87A and connect it to 87

Posted By: tedmond
Date Posted: March 02, 2008 at 6:45 AM

this is how you will wire it if you want it to work when ground is sent. you will have to cut the starter wire in half.

85 - ignition 1
86 - GROUND from switch
87 - Starter wire key side (towards key cylinder)
30 - Starter wire Motor side (towards car)

do you have a aftermarket alarm on the car? or you just adding the starter kill to be protective?

Posted By: tedmond
Date Posted: March 02, 2008 at 6:51 AM

aww 3 min too late ahah. well just to add, i suggest you do a STARTER KILL, not an IGNITION KILL. There are ups and downs to doing a ignition kill.

Posted By: boostaddict
Date Posted: March 02, 2008 at 11:50 AM

I don't have my alarm installed yet. I'd like to do a stealth kill till I get my alarm installed. Why do you prefer a starter kill over ignition? It's still push startable if I just kill my ignition.

Posted By: boostaddict
Date Posted: March 02, 2008 at 12:00 PM

I mean they could still push start it if I kill my starter.

Posted By: tedmond
Date Posted: March 02, 2008 at 8:50 PM

what car? if you break the start wire there is no way of starting it.

Posted By: i am an idiot
Date Posted: March 02, 2008 at 9:22 PM

If he has a manual transmission, the car can be push started if he uses starter kill. That is why he is killing ignition.

Posted By: boostaddict
Date Posted: March 02, 2008 at 10:26 PM

Yeah I have a manual S13 240sx. Just waiting for a couple harnesses then this will be all wired up. Thanks alot "i am an idiot" for the quick reply and help. As soon as I get my proximity sensor and back up siren, I'll be installing my 50.5x, so you guys will be hearing from me again for help on that one. posted_image

Posted By: tedmond
Date Posted: March 04, 2008 at 8:22 PM

hey i am an idiot can u explain the term push starting? thanks

Posted By: i am an idiot
Date Posted: March 04, 2008 at 8:29 PM

I will try, If you have a manual transmission vehicle and your battery is too low to turn the starter and power the ignition at the same time. You can turn the key to the run position. With you in the car, get 2 of your boys to push the car as fast as they can. When they reach their maximum speed (5 MPH will probably do the trick). You put the transmission in 2nd gear, and move your foot off of the clutch. Do not slowly let the clutch disengage, you must release it quickly. The car will now start. This procedure works if your starter is defective also.

Posted By: tedmond
Date Posted: March 05, 2008 at 11:35 AM

so insted of doin ga starter kill on a manual would you end up doing a clutch kill ex break the continuity on that wire? or ignition is best.

Posted By: i am an idiot
Date Posted: March 05, 2008 at 7:02 PM

to prevent theft, ignition kill is the only way to go. There are safety issues with ignition kill. Suppose the driver is pulling onto the freeway and the connection you made on the ignition wire fails, he is dead in the water. The relay could fail also. I know they are not prone to failure, but I have seen them fail. If the connection or relay fails on starter kill, he just can't start the car. That would only be a problem if he was robbing a bank.

Posted By: tedmond
Date Posted: March 07, 2008 at 2:36 PM

ahah alright thanks for the info bro, thanks !

Posted By: dualsport
Date Posted: March 14, 2008 at 12:26 AM

i am an idiot wrote:

That would only be a problem if he was robbing a bank.

That made me laugh posted_image

Never thought of that safety aspect.