My Suburban's AC comp clutch cycles on and off in 5 sec intervals at least 10 times. Around the tenth cycle the compressor will not engage at all. The digital climate control will then flash "AC" over and over. I disconnected and reconnected the battery and it did the same thing. I then disconnected the switch on the Dryer Accumulator and jumped the harness. When I did that the compressor and AC system functioned normally. There is one of two things going on...either the switch is bad or I am low on refrigerant. In event it is the refrigerant, can R12 be mixed with Freeze 12?