DEI 528t, Siren Delay

This is a circuit I'm using in my truck that's triggered by the siren output of the alarm.  It delays output to additional alarm lights and sirens.  Right  now I have two Aux relays that control two circuits that are isolated from each other.  One for LED's and one for an additional siren.  These lights and siren needed to be isolated because they are also switched on manually and cannot be allowed to backfeed into each other.  I originally tried it without the 'Delay' relay, but found that the 528T was pulling the Normally closed circuit open at the same time that the Aux relay was closing, resulting in a very brief flicker of the LED's.  With the additional relay inserted, the flicker is eliminated.

 

Result:

 

Arming and disarming chirps only use the car alarm siren.

During full alarm, and after a two second delay, LED's and secondary siren are activated.

 

I hope somebody will find it useful.

 

Hoot