Problem with keyless entry setting off alarm

[cshuntley]

Hi, I'm having a problem with the keyless entry pad setting off the alarm system. I bought the truck used but, I'm pretty sure it is a factory alarm system. Once the system is armed, as soon as you press the first number the alarm goes off. If you complete the number sequence the doors do unlock, but the problem is the horn keeps honking. Is anyone out there familiar with this??

 

[jad2411]

Ford did not offer an alarm system, so the factory keyless entry pad will not disarm the other alarm, that's why it's triggered