That happened to my 8012-3s. All I did was start the programming sequence. I first held full throttle and waited for the beeps and then full brake after the beeps. I then applied full throttle for each mode until it was over. That seemed to restore my full throttle and full brake and the controller worked fine. Afterwards I did the programming again to set it parameters that I wanted.
OK; tried that; no luck. I've pretty much resigned myself that it doesn't work, that I'll have to toss the controller - and be out $550 on 2 MGM controllers and start from scratch with a Quark, which I should have just gotten in the first place.
My new MGM 16024 that I just got from Mike is doing the same thing, I also have not been able to figure it out, however I don't think it's broken I think we are doing somthing wrong. I also gave up on mine because I got so frustrated.