ABS light comes on and my fan to A/C, defrost will not work

More test results are needed to make a diagnosis, but since the ABS warning light came on, have the diagnostic fault codes in that computer read and recorded. If there are none, you might consider the ignition switch. If there is a burned contact in it, that could cause intermittent operation of whatever is on that circuit. This problem often involves the heater fan, especially for people who use it or leave it on the higher speeds a lot. Those motors draw a lot of current and can stress the contacts in the ignition switch.