purchased a 1996 for mustang convertible GT for my daughter. whenever we unlock the drivers side door and open, the horn honks over and over. wont stop unless I pull the positive off battery..this is not a keyless entry. any ideas out there on how to stop the madness....

 

Look for an after market alarm box under the dash.....along with a lot of add on wiring.

 

Yeah, it sounds like an aftermarket alarm system is going nuts. This is quite common.

btw, don’t pull the positive battery cable. It is better to pull the negative battery cable due to less chance of shock, spark and/or arcing.