Horn goes off w new battery

When main power is removed the security system is triggered automatically, there is detailed information in the owners manual on how to deactivate your model specific system. Usually you can use the key fob with the horn honking push lock then unlock and it will reset. However there are on rare occasions when the security system locks all signals out and can only be reset by the dealer.

The security system was active when the battery died or was disconnected. Do as Ed said or, if you don't have the fob, lock and close all the doors with the battery disconnected. Now connect the battery. The horn should not go off. Use your key to unlock the driver's door and hold it in the unlock position for a few seconds until the other doors unlock. Once that happens you should be ok. Hope that helps! Jim