Air Bag - Interesting Observation

[930turbo]

I get an occasional air bag light on my 2001S, driver side seatbelt buckle. I have the Durametric cable so I can easily reset it, which I've done several times. I have the service history where the previous owner paid significantly to replace the buckle so I believe this has been an issue for a while and the buckle didn't fix it. What I have discovered is the air bag light only occurs after the car has been jacked up off the ground. It's on after every oil change, tire change or any service off the ground. Most recently I installed wheel spacers one wheel at a time and upon completion the light was on again. It's too consistent to be coincidental. Has anyone else experienced this? I see mechanical ride height monitors on the suspension, could they somehow be related to the air bag?