the OEM alarm won't shut off
 

2007 Crossfire coupe 6 speed 142k miles
It all started with what I thought was dead batteries in the key fob. Went to work in the morning and the fob locked the doors just fine. After work it doesn't unlock the doors. So I use the key to unlock the door and the oem alarm trips and the siren goes off. Typically you put the key in the ignition and the siren stops, but not on my Crossfire. Wait for the alarm to reset itself and then try to start the car. Nothing. All lights work. I tried doing the whole resync the key fob and that doesn't work. I tried pulling the #13 fuse which the alarm system is on and the siren stops. I can also start the car and it runs just fine. Thinking that this might just be a low battery I drive it home and charge it to 100%. I put the #13 fuse back in and the siren immediately starts blaring out! I pull the #13 fuse to stop the siren. With the #13 fuse pulled out I can push the lock or unlock button on the fob and the lights blink but the doors will not lock or unlock since they are in that same fuse.
I am wondering if anyone has some new ideas for me. I'm thinking that maybe the "Immobilizer remove" scenario might fix this problem. What do you guys think???

Re: the OEM alarm won't shut off
 

Are you sure you are looking at fuse 13? It is usually #9. With the (?) fuse in place and siren blaring, disconnect the battery for a minute. The anti theft alarm should reset, reconnect the battery.

Re: the OEM alarm won't shut off
 

When people usually talk about "Immobilizer" then mean the SKREEM. This is not a SKREEM problem. You may have a faulty battery in the siren under the plastic cowl under the windshield. If resetting doesn't work. I would remove or replace the siren.

Re: the OEM alarm won't shut off
 

It's the weekend. Have you had the time to try the first two suggestions? There are a couple others, but it's best to do those listed above first.