Owners/service Manual problems of the 2000 Chevrolet Cavalier

After purchasing the vehicle we wanted to put a different radio/cd player in it. When we went to do so, we discovered that if the factory installed radio was disconnected, the airbag deployment sensors no longer functioned. This is not mentioned anywhere in Chevrolet literature. This, I believe, is a safety issue. I learned after two days of research that if the factory radio is even removed for repairs, it must be replaced by another factory radio or the airbag deployment senors again will not work. Chevrolet should make this fact clear in its sales literature. This affects 2000 and newer Cavaliers. I do not know if this is the same with other gm model cars.