Car Alarms: car alarm 2002 tahoe, gm system, voltage spike

Question
QUESTION: I have a factory alarm and another alarm on my 2002 tahoe. The 2nd alarm has been disabled.  A few days ago, i left the store and unlocked my truck with the remote.  I then cranked it and the alarm sounded twice.  It has done the same thing every time i crank it since then.  I have even tried with the remote, to lock and unlock the doors, but it still does it when i crank the truck.  What is causing this?

ANSWER: If you mean the siren on the
after market alarm still chirps, then
the system is picking up a stray voltage spike allowing
that to happen.

If however the siren is sounding teice when you crank
it over, the same holds true. The OEM-GM system
is spiking or feeding back through the aftermarket wiring
and you get the chirps.

You said the 2nd one was disabled.
Can you explain to me what you did to
accomplish it? I may have more to offer.

ALARMTEK
CARALARMINSTALLER.com

---------- FOLLOW-UP ----------

QUESTION: We had the second system professionally disabled, it would not let my truck crank one day.    As far as the alarm, it is the actual alarm, not the chirp. It makes just two sounds(like when it goes off continuously).  It does this not when the key is inserted and turned to the first position, but when it is inserted and actually turns the truck over.  I am not experiencing any other problems...   the fuel is not shutting off, the door locks work accurately, the chirping with the remote and all lights and security sensors work correctly.

Answer
Hmmm, ok, how about you try to reset
the aftermarket alarm for me to remove
it from this equation?

Key on, press and hold in the valet/overide button
found under the dash area until you get a chirp,
and the LED in the dash comes on solid.

That's valet/overide.
Then no chirps at all.
This should relieve the problem.

See if the trouble is related to this overide.
It sounds like "reporter" chirps.
Like the alarm was breached, and it's trying to notify
you of that.

Try the resetting procedure and let me know if
it applied to this situation, and if there's
any joy there.

A.