If this behavior only occurs when you use the driver's door lock cylinder, then you probably have a bad microswitch in that lock. You can either have the cylinder replaced, or you can disable the alarm system. It's your call. BTW, if you only disconnect the horn, the lights will still be flashing..
2000 Dodge Grand Caravan SE
[This message has been edited by jeffsr (edited 11-03-2000).]