Own F-150, 1997.
Sits out during winter. I started periodically to keep battery up. Left it too long this time. Dead battery. Took it out. Wouldn't charge. Bought new battery. Installed it. Immediately, upon attaching the second cable to the battery, the theft alarm blasts my ears out. Owner's guide says unlocking door will stop the alarm. It didn't. Says turning ignition key to on position will stop it. It didn't. Of course the truck won't start because relay to starter (I assume) cuts off that option. Is there a simple fix or will I have to have the truck towed to dealer or shop to have work done?

 

Hi Jim- don't hit me for asking what will seem like a stupid question but you did this with the remote, right? I have never seen an alarm that wouldn't shut off (upon connecting the 2nd battery cable) when the unlock (or disarm) was pushed. I always kept the remote in my hand when I connected the 2nd cable so I could immediately shut it up. If that doesn't work I would disconnect the battery a 2nd time, let it get it's little brain unscrambled and try hitting the unlock as soon as you connect the 2nd cable. Let us know what happens. Y/T- Roger

Jim- I can't fully explain it but I have seen it enough times- often when a battery goes fully dead and is ether jumped or recharged there are electronics that "flop"- (change sides if you understand what I mean) and have to be triggered to "flop" back to where they belong. That's what I was trying to get across with the disconnect and reconnect. Y/T- Roger