Car Alarms: anti theft systems, brain box, car wont start

Question
i have an 07 cobalt ls with a passkey||| alarm system. i was changing the head unit and the wiring harness has a brain box attached to it when i hooked it up it activated the anti theft system and now my car wont start two lights are lit up on the dash when i turn the key the check engine light(always on)and the theft system light. my car dosen't have a key less entry or remote for the alarm i have disconnected the battery and left it on overnight and that didn't work. any and all suggestions are highly appreciated thank you very much.

Answer
The problem is from my view, and what we do here,
unless you can start it to program a bypass,
I don't have an answer that will work for you.

The trouble is that the PLJX passlock bypass module
needs to have the car start long enough to program
it. We do this type of this for remote starting.

The best thing here is to call dealer service dept.
& have them reset the code to at least start it,
then install and program the
PLJX module to circumvent it for good.

That's how it's going to work.

If you want to proceded,
CLICK HERE to purchase.

Regards

ALARMTEK