How to wire a sensors and siren to a RS795VAT REMOTE START AND ALARM

copy and paste
https://www.alarmgrid.com/faq/how-do-i-add-a-siren-to-my-honeywell-vista-alarm-system

What sensor are you wanting to hook up? Does the sensor have a pre-warn feature, or is it a 2-stage sensor? These have an extra wire compared with a single stage sensor.

install like a regular remote start alarm. You will have to tap into the glow plug wire, and change the setting on the brain to "wait to start" for the glow plugs.

If you have not installed a remote start alarm before:
1.install the siren under the hood and run the wire through the fire wall into the cab.
2. Mount antenna at the top center of the windshield then run wire around and down to drivers floor.
3. mount shock sensor with a ziptie to the steering column (as long as the steering column doesn't move/rotate)
4. separate the wires you are going to need, from the ones you won't need.(specific per vehicle):12+, Gnd, Parking lights, IGN, IGN2, ACC, ACC2, Starter, lock, unlock, brake, glow plugs...
5. zip tie and tape off the unused wires.
6. use wire diagram and find then test the vehicle wires.
7. connect RS/Alarm to vehicle, plug in antenna and shock sensor, then attach siren.
8. BEFORE DOING ANYTHING ELSE-GO INTO PROGRAMING AND CHANGE THE SETTING FOR A DIESEL !
9. now you can test the functions of the RS/Alarm,
BE SURE TO KEEP A WINDOW ROLLED DOWN, OR HAVE A SET OF KEYS OUTSIDE THE VEHICLE!

from the siren 2 cables come out, one black and the other red, the red one goes to the siren output (brown wire)

take off the siren and connect it to the battery, if it works check the alarm wiring. if the wiring is good check the output of the siren.

The alarm may not be going off. Rather it may be a malfunction of the relay that is driving all the sirens and piezo. Next time it happens check for flashing parking lights. They will flash only when alarm is going off. Also ignition input to the alarm prevents this alarm from going off while driving. Panic from the remote can still be triggered. Got to play detective....

First thing is to trip the system to see if the siren works then. If it does, then perhaps you inadvertently set the chirp commands to silent. If the siren doesn't work when the system is tripped then that's your problem. You'll need to find the siren and troubleshoot possible causes. I'd start with the wiring but the siren could have simply gone bad. You should be able to test it easily with a test light or multi-meter.

disconnect the 5 pin harness, it has a red, brown, black, white, and red/white wire on it.
the brown wire in that specific harness, is actually the wire that runs to the sirens RED wire.

An output wire is not connected, you'll need to connect the brown wire on the 12 pin harness to the siren, it will be pin number 10. Either that or your siren is bad.

Try to panic the alarm if that does not work then your siren is probably bad also check the wiring leading to the siren to make sure it is connected......