Gary,
I can't speak for your 1999, but I had an issue recently with a 2005 GV [
see post #2 here ]. I've no idea if your model even has a BCM or an IOD fuse but maybe in the absence of any better ideas being put forward try :
- disconnecting the battery for a few minutes or so
- then re-connect
- part 1 -then put the key in the ign [without starting the engine
but with the ign turned on]
- part 2 -while the key is in the ign power lock and power unlock the doors from the fob
The idea basically is to erase any miscommunication between the remote keyfob and the car then re-establish the communication when locking and unlocking the doors whilst the key is in the ign and recognised by the car.
_____________
Also -
found this for your year on Google I have no idea if it works :
1997 to 2003 Caravan Programming Instructions
1
Press the "Lock" button on the functioning keyless remote five times, with a two-second interval between each press.
2
Insert your key into the ignition; turn it to position "3" (Run), without starting the engine. Leave the key in the position until the warning chime stops beeping. This will take a minute or two.
3
Press and hold "Unlock" on the functioning remote for about five seconds, and then press and hold "Panic" as you continue to hold "Unlock" for about one second; release both buttons. After a few seconds, you will hear a chime.
4
Press and release "Lock" and "Unlock" simultaneously on the functional remote, and then press and release "Unlock" by itself.
5
Press and release "Lock" and "Unlock" simultaneously on the remote you want to program, and then press and release "Unlock" by itself.
6
Turn the ignition to "Off" and remove the key to exit synchronization mode.