My mom has a 2002 Lexus RX 300. Every time she arms/disarms her factory alarm I love the simple little tone that it give's off. Is there any way I can just goto the delearship and order the horn/siren thingy that makes this noise and then hook it up to my existing alarm? or is this alarm tone build into the vehicle? I looked at a lexus parts site and couldnt find the siren part. Any one know?

 

Yes, it can be done. Just get the the siren peice from there alarm. Go to the dealer and order it.

 

Got a part # for me? The dealer doesnt seem to be able to find it...

 

If I remember right its the whole system siren

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Type Ek &raquo;</TD></TR><TR><TD CLASS="quote">Got a part # for me? The dealer doesnt seem to be able to find it...</TD></TR></TABLE>

Maybe you should try another dealer, since this one is apparently incapable of doing their job?

 

OK, I got the siren but its actually a high pitched horn. I hooked up the 12v line to the alarm and have a really good ground but it wont work when I arm/disarm the alarm. My alarm output is 12v and the horn is 12v so I dont understand why it wont work? Do I need more power to activate the horn? When I hook my siren thingy to it, it works but the horn makes no noise...Any help?

 

What happens when you pulse the 12v input to the siren?

 

The siren works (it chirps) but the lexus horn does nothing. The only way i got the horn to go off was wire it directly to the vehicles battery, but that doesnt help because its obviously a constant.

 

Use your alarm's siren output to trip a relay. Have the relay send battery power to the siren.

Did they give you the damn car horn or the alarm siren? Or are they the same, like on Fords?

 

Cool thanks for the idea...what kinda relay would I use? Lexus alarms have 1 low pitch horn for the vehicle horn and a high pitched horn for siren of the alarm.

 

SPDT auto relay of course. SPST would work too.

Alarm's brown to 85, ground 86.
Siren power wire to 87.
Battery to fuse to 30.
87a not used

I'm not sure how many amps the siren pulls, probably a lot if it's too much for the alarm. But certainly not more than 5. Anyway, you're fine using a 5 or even a 10A fuse.

 

btw... where are u putting it?

and do you have back-up sirens?

cause i learned the hard way... that we should all fuse the siren out lead as close to the brain as possible.

or just fuse each split of the siren out lead.

that way if a thief pulls your main siren out to quiet it down.. and some how the ground and positive cross... and short... your backup sirens still work.