I need help with my 2002 Mitsubishi montero limited.

The battery went dead so i replaced it, and now the alarm goes off whenever the key is put in.

However None of the electronics work when the car is opened or closed or on. Like no power locks/windows/lights etc so i cannot put the driver key in and lock it twice to reset the alarm.

It will start run and drive but the alarm keeps going off and no electrical options will work in the car.

I have tried resetting it by the battery cable method but that doesn't work.
I tried making sure all the door and door locks were locked and no jambed etc but they are all fine.
I undid anything aftermarket that would cause voltage drop( i only had a cb and that was all the aftermarket).
I do not have a key fob for it.

Anyone have any advice? I could really use some help with this issue asap.

Thanks all.

 

Ever get your problem with the alarm diagnosed? I have a somewhat similar problem with my alarm but do not have the electronic issues. My alarm just goes off in the middle of the night for no apparent reason. It only happens once and a while. Used to think someone was trying to break into the vehicle. Thought I was going to get to use my 357 but alas it was only a faulty alarm system.