Starter Kill Relays Killing Battery

Hi All,
I have an '01 Blazer that is my secondary vehicle so it doesnt get driven much. The starter kill relays put a pretty bad drain on the battery between the times I use the car. I come out to the vehicle and the battery is dead (you can imagine how fast that gets old) I may only drive it once a month or two months.

My alarm is an Autopage RS-855. It has an ORG wire that grounds when ARMED and an ORG/WHT wire that grounds when DISARMED.

Here's the brain teaser: What I'd like to do is devise a system where the relays are energized when needed instead of being energized 100% of the time. This would minimize battery drain. I want to devise this for both the ground at arm wire AND ground at disarm wire. I have come up with a schematic that I think should work well for the grounded when armed (ORG) wire (see pic below). But I can't think of the best way to do it with the grounded when disarmed wire. As for triggering the ground at disarm wire, what should I use? (key sense wire maybe?)

Please let me know what you think of my diagram (any issues/problems with it?) and what you would consider for grounded at disarm wire where the relay isn't on all the time.



The YEL wire is the starter wire. So on the top relay, the relay would only be energized when armed AND a thief put 12V to the starter wire. If that happened, the relay would separate the starter wire. Otherwise the relay is dead and not draining current. Below that you could optionally put a relay that would disconnect the fuel pump also. Sorry for the archaic picture   : )

Thanks guys!
John

You are making it way too complicated.

86 - ground when armed
85 - ignition
30 - starter wire key side
87a - starter wire starter side

I dont know if I'd call it complicated. I'm not a car thief so I'm not sure what all wires need to see 12 volts in order to start a car?

(A) Would a thief have to give 12v to all IGN wires and the starter in order to get it to start?

(B) Does my method pose any issues?

(C) Any solution on how to do a starter kill with the grounded at disarmed wire (where relay is not always on)?

Thanks

calee4nyaboy wrote:

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(C) Any solution on how to do a starter kill with the grounded at disarmed wire (where relay is not always on)?

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JWorm gave you Relay hookup that is NOT On until you Start the Vehicle

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MO

Don't Learn from Others Mistakes
You Might Be the One That Knows.

mo12v] wrote:

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calee4nyaboy wrote:

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(C) Any solution on how to do a starter kill with the grounded at disarmed wire (where relay is not always on)?

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JWorm gave you Relay hookup that is NOT On until you Start the Vehicle

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My scenario already doesnt engage the relay until a start attempt has been made. But thats WITH the alarm ON and ARMED. My scenario is just about the same as his.

Question "C" is about how to do a starter kill when the alarm is DISARMED. This would be using the "grounded at disarm output" of the alarm and some other input to the relay. The question is what other input would provide this? I've never had to mess with any key sense wires so I dont know what signals (ground or 12v) they give out and at what time. So I dont know if key sense would be good to use or?

I don't do alarms full time or anything but there are some really crafty people on here with wiring...someones got to know the answers to A, B and C.

I wouldn't want the Fuel Pump disabled, just Starter & maybe Ignition........

Ign Key Warn

L GREEN (-)

STEERING COLUMN HARNESS

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MO

Don't Learn from Others Mistakes
You Might Be the One That Knows.

The Passlock II disables the fuel system so I dont mind doing it. I may or may not. It's just one more deterrent. I live in the south and there is crime everywhere here. But I'm more worried about the relays not being energized 100% of the time.

But the fuel pump relay diagram, if not modified a little, would be a problem because if you auto-started the car, the YEL wire would feedback 12v to the fuel pump relay energizing it, which would cut the fuel pump off.

Has anyone ever used the key sense (-) wire to energize a relay? (to pin 85 or 86)

Typical automotive bosch relays consume about 140-150 mA to energize the coil. Is that too much current for that little, tiny key sense wire OR whatever it's attached to (like the BCM etc)

I dont wanna fry the key sense circuit(s) by over loading it.

Okay, I found that you can energize a relay with the key sense without messing things up.

Does anybody have any thoughts on the 3 questions (A, B & C) above??

Here are a couple solutions that do not require an alarm: https://www.the12volt.com/relays/page2.asp#psk 

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the12volt • Support the12volt.com

if you are worry about your vehicle being stolen. you wanted to use a relay to cut the starter wire off when the alarm system is off. that's the easier solution. Have you ever consider using a positive trigger instead of using a negative trigger.

remember, the starter wire only required 12+ volt to starter the vehicle. once the vehicle is started there is not current going to that wire.

Relay:
87 -- 12+ volt 30 amp fused
87a -- starter wire Key side
30 -- stater motor
86 -- Ground (or key sen wire)
85 -- Ignition wire (or rear defoger wire, or high beam wire, or head light wire, or parking light wire, etc. etc.)

good luck