I have rare problem with my 2001 Z3, the airbag light comes on and goes off after leaving vehicle for a couple of hours, and comes on after a drive on restart.
I had my friend hook it up to Snap On Modis scanner while the light was on, there was no communication.
I let the vehicle set overnight and the ligth was off, took it to him again and the scanner had communication, but; no codes.
Drove the car for few miles and restarted the vehicle after get gas, Light ON again and scanner conneted no communication.
disconnected airbag harness in 3 different places, both seats (under) and also under dash and reconnected. Same problem.
Anyone can help here.