I'm pretty sure '91 models didn't come with an anti-theft system. Those require a Body Computer, and '92 was the first year for those in the minivans. If you have a late production '91, it might actually be a '92 model. If that is the case, the anti-theft system is turned off by unlocking a front door with the key. When that doesn't work, it is almost always due to broken wires between the door hinges.
What are the symptoms when you open a door and when you try to start the engine? Can you hear the hum of the fuel pump for one second when you turn on the ignition switch? Chrysler didn't use chips in their keys. That's a GM thing.
SPONSORED LINKS
Tuesday, June 29th, 2021 AT 8:21 PM