Hi Andrew, I might be wrong in this so will have to check but the way I think it works is this.
1 - Car unlocks
2 - Doors open, interior lights open and ECU registers open doors.
3 - On open door register, then ECU asks question on occupancy on seat.
For example, I have opened the passenger door and put a heavy box on the seat and the seat belt light has come on. If I get in the drivers door and pass the same heavy box over and put it on the seat, the seat belt light stays off.
Again, this could be just because I have a faulty seat occupancy sensor rather than the process checks of the ECU but once I bypass the Seat Occ sensor I am about to find out if I am going to get the annoying seat belt warning noise.
