Rav won't start now

Short story Long.......... 2001 Rav 4

We jumped into the Rav to take the dog to the Vet after she had a seizure. click click click ...so I get my truck to jump-start. Battery is so corroded and covered in powder it's a no go.
Now to unload the truck, carry dog, etc........

Upon our return I figure a nice cleaning will help the Rav, everthing goes well, I go to open the driver and the car alarm goes off. WTF !
12 years and I never heard the alarm til today. We don't have an alarm key or anything, didn't even know the alarm was hooked up.
How in the hell do I turn it off?? I pulled the alarm horn, the little red blinky light, now it's quiet, but the blinkers are flashing, and vehicle will not start. Not even a click.

Any one have a clue?? I followed the wires to behind the fuse panel in the cab.

 

Follow up ...........

Thanks to google and other sites, I was able to locate the alarm unit and all it's wires. Once I looked up the units name I was able to find many useful things except how to remove the F***** thing. Maybe a good thing.
I now had the choice to order an after market remote for $30.00 , or tow vehicle to an installation place that would charge $65.00 for removal. Wife has free towing with USAA so we opted to get rid of the unit.
Vehicle starts, everything works.......AND best of all, I am going to use the PA Siren horn on my motorcycle. That's one loud Mother