if the airbag light is not associated with the power seat wiring underneath. what would be my next guess?
Well my first guess is there is a problem with the air bag system. One common problem is a sensor error. I don't know about your '99 Venture, but most if not all cars have a build in system to tell you why the light is on. How you read it depends on the car, so hang in there until someone who has that information for your car post the information.
I doubt if you currently have working air bags.
There is no need to guess. Every airbag system has a controller, or computer, that controls airbag operation and the warning light. A technician can access this controller and get its code to help identify the malfunction.
You won’t be able to solve the problem or shut off the light (let alone expect the airbags to function) until you have someone start by accessing this trouble code.
i’ve been hearing things from gasket to seats to sensors… maybe timee for the mechanic