Mystery switch

1999 Chrysler Town & Country There is a small toggle switch - the kind that would be used on small electronics with a bat toggle) below the dash and steering wheel next and to the right of the connector for access by an error coder reader. Reasonably thorough reading of owners manual doesn’t show it; doesn’t even seem to reference the connector.

What does switch do?

It could do any number of things. It might turn off the OBDII connector power or it might be a simple…but effective…theft deterrent system. It was probably installed by a former owner who understood how to read a wiring schematic.

Ejector seat? Oil spray? Tag indexer?

Or maybe an auxiliary fan is on the radiator/condenser.

The previous owner installed it. Is there fog lights mounted on the front of the vehicle?

Could be a switch for the tail lights for stealth but you’re just going to have to flip it and see what happens.

Theft deterrent switch for an after market theft deterrent system. When I bought a used Malibu it had the same thing. I wouldn’t advise messing with it. It could make the car unstartable if you don’t know the proper sequence to reset it.

I had a toggle switch like that in a Ford Maverick Grabber that I once owned. It was factory equipment, but I bought the car used and it had no owner’s manual. The switch turned on two lights mounted in the grill that were so dim you had to light a match to see if they were on. I never knew what the lights were for, so I had a mystery switch that turned on mystery lights. (The garage that serviced that Maverick told me that they were “sport lights”).
Years ago, when I was a college student, I worked in the summer in the audio visual department of the library repairing equipment. One day, the janitor of the building came down and asked me to help him by being available to regulate the air conditioning if there were complaints. He took me to the mechanical room, gave me a key to the room, and showed me a switch. “If you get complaints that it too warm, flip the switch to the opposite direction. If you get complaints that is too cold, flip the switch in the opposite direction. Be sure that the person who complained sees you flip the switch”.
“What does the switch do?” I asked. “Absolutely nothing”, the janitor replied. "I installed it myself. However, the complainer doesn’t know that. Just tell them that the temperature will be fine in five to ten minutes ". It worked.

LOL, I have one of those on my dash. I installed auxiliary LED lights to better light my gage cluster, but it didn’t work. The light simply reflected off the cluster and made visibility worse. I disconnected the wiring, but the switch remains as a tribute to a failed attempt.

Perhaps a previous owner of your vehicle did the same.