With seat belt interlock system.
This system prevents a vehicle from starting unless the seat belts are fastened. But it goes beyond that. The seat belts must be fastened within a specific sequence. For example, the driver (and front seat passenger) must get into the car, close the door(s), sit down, and then fasten the seat belts. If the seat belts are not fastened, or if they are fastened in an incorrect order, the car will not start.
All 1974, and early-to-mid 1975 vehicles had the seat belt interlock system.
HOW DO I IDENTIFY IF MY VEHICLE HAS/HAD THIS SYSTEM?
All 1974 vehicles had the seat belt/starter interlock system. As for 1975 vehicles, unless you arethe original owner or know the history of the
vehicle, unknowing wiring modifications by previous owners or repair shops can make this identification difficult. We suggest trying to locate the
specific components of the interlock system within the vehicle.