Factory remote start wont work. hit button horn bbeps all lights and radio come on. when horn beeps second time car wont crank as it always has in the past

To arm content theft alarm.
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The
SECURITY light should flash.
3. Close all doors. The SECURITY light should go off
after approximately 30 seconds. The alarm is not
armed until the SECURITY light goes off.

If a locked door is opened without the key or the remote keyless entry transmitter, the alarm will go off. The headlamps and parking lamps will flash for two minutes, and the horn will sound for 30 seconds, then will turn off to save the battery power.

I would return it to the installer

My 2012 Hyundai Elantra Wont Start - CarGurus

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CarGurusJul 30, 2013 - My 2012 hyundai Elantra GLS would not start this morning. ... I hit my door unlock on mt Key fab and the doors unlocked fromt here I proceeded start my car.... it and it wont turn over just makes a light click. not like a battery issue. .... But if Istart from the zero position on the starter it doesn't start on the first try ...

No horn / No lights when I lock my car - Hyundai Genesis ...

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Mar 30, 2014 - 16 posts - ‎8 authors
I do not know what could have caused this but when i lock my car... ... lock yourdoors with your key fob(might have to hit the lock button twice) ... The alarm/horn should start beeping. ... 2010 Hyundai Genesis Coupe 2.0T R-spec in Karussel White.... My lights flash when I lock it, but the horn doesn't sound.

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The 2013 Hyundai Elantra has 19 complaints for engine won't turnover, won't ...

is it in park or neutral as that will not allow it to start

this happened to me in one of my cars, I bet that if you put the factory radio back in it will work just fine, most of the radios components, are part of systems wiring and used to send signals to ecm to let car start

Have you checked if there are any mega fuses that went, maybe a shorted harness or bad relay?

Check the owner's manual; many factory alarm system self-arm after a limited time-out. And, a combination of buttons on the remote will often select either silent arming or a horn-beep/light-flash to let you know.
If you want to check if it is armed, you could always use the flat hand on your hood after you think it is armed with the remote.

holdboth the lock and unlosk buttons on your remote simultaneously for about five seconds until the lights flash and horn chirps.that should do it.if not i believe these models used a separate horn for security system.possibly fuse for this horn is bad or the horn itself is bad.to see if this horn works lower drivers window.stand outside vehicle and lock doors with remote.wait about a minute and reach in window and MANUALLY unlock and open door(do not use power door lock button)this should cause the system to activate...horn should beep and headlamps should flash.if horn beeps try my first suggestion.if it doesnt beep and just the head lamps flash check fuses and horn for security system.

Setting can be accesed through the radio to change options. Follor the owners manual.

the jetta has a faulty alarm system from the factory i have been working on one in my shop. the alarm moddule is inside the dash behind the light switch and has a 10 pin connector and a 6 pin connector. this can be bypassed if you disconnect both connectors and jump the two large wire on the 6 pin connectors, these wires operate your starter. the car will start and run but your alarm will no longer be active. the door locks and everthing else will still work. the only issue i am having is the factory radio isn't working because it is controlled by the alarm. but worse case scenario i can use an aftermarket radio if need be.