Remote start + siren

if i dont have a siren output but have a light flash output how  can i hookup a siren to go off when i lock/unlock doors. right now i get light flashes to display door locks/unlocks. how would i go about hooking up a standard siren to that?

Maybe some one knows but with out info on the unit and car we will have to acll Miss Cleo to fing out the answer.

hook up a siren to a relay with the parking lights isolating them so the siren only goes off when arming and disarming

-------------
There are 10 types of people in the world, ones that understand binary and ones that dont.

Like said above.

If your car/truck only needs low power neg to activate the lights then just put a diode beteen the alm and the light wire. On the alrm side of that same wire connect the siren. ONLY if the wire your are connecting to drives a relay or computer input.

If it carries the power then I'd recommend 2 relays. Use the wire from the alarm to activate both relays at the same time. On relay sends power to the factory light wire, the other relay to send power to the siren...

sorry i cant believe i didnt put in the car info.... its a 1998 blazer and i have it set to give a positive pulse to activate the lights. floater could you point me to any diagrams perhaps, im not really good at knowing how to hook it up w/o diagrams...
thx so far...

Is it set up with an external relay for the parking light pulses? If it's internal, it'd be harder to do, unless you have large diodes or want to get inside the alarm module.

the remote start has a white wire coming out of it that is fused 12 volts that i ran to an external relay to the parking lights wire.

Does the remote start continually flash the parking lights while the engine is running? 

Yeah, that would be kinda annoying after a while, wouldn't it-
If it only flashes when doing the lock/unlock, then it'd be easy, otherwise you'll have to gate it out when it's in RS mode.

yes i believe it does, and yes that would suck quite a bit if it did that.

is there any way i could hook it up to the door locks then??? thats all i want it for is so i know when my doors are locked or unlocked. i have 2 external relays for my doors which are 3 wire + pulse.

What if you used the parking light to control the relay for your siren, with the other side of the coil connected through a diode to the ignition run line?
Then it wouldn't go off when you're in RS mode, but it would when the car is off.
Only drawback is that you couldn't turn on your parking lights while the engine is off without your siren going off. It'd be a good headlight reminder though- you won't leave your headlights on by accident for sure..

no i need my lights for sure, thats the only way right now i can tell if its locked or unlocked when i click the remote.

jesus there has to be some way to make this happen... thx for help so far

That's basically the idea, use the ignition run line on the other side of the coil, so it acts as the ground return for the relay when the car is off. When you're in RS mode, it'll be high, and the relay won't energize, even when the parking lights start flashing, and the siren will remain silent. You need to put an extra diode inline to prevent the siren from going off when you have the ignition on and the parking lights off. (Diode stripe should go towards the IGN line)
It doesn't disable your lights, if that's what you were concerned about; you're just using the parking light feed to power up the relay during the lock/unlock period.

If you have any situations where you want the parking lights on without the engine running, you may want to just put in a switch to manually allow this without having the siren go off. Normally you wouldn't want the parking lights on without the engine running, so I don't thing that's a problem.

well the thing is is that i want my parking lights to flash when i lock or unlock the doors as well as activate the siren. my unit is a Valet 551r or something... very close at least

This is what you could do.


If you want to leave your lights on with the engine off, then you should put in a switch to manually disconnect it, to prevent the siren from sounding off when you do that.

where does 87 a lead out to. just no where? other than that it makes sense, just tap the parking light wire and put i diode inbetween? just wondering why need the diode?

You don't need to connect the 87A terminal; the single pole double throw (SPDT) type of relay just happens to be the most common one used around here, so I used that.
You can use a SPST relay if you have one, which doesn't have a normally closed contact.

The diode is so that the relay won't go off when you turn your ignition on and the lights off. If you didn't use the diode, your siren would go off while you were driving unless you turned the lights on.

Any time the relay control inputs (85 and 86) get a difference of 12V, it'll energize and close the relay; it doesn't matter which one is 12V and which one is ground. The diode just keeps it from energizing when the tables are turned, when there's 12V on the ignition and 0V on the parking lights.