car just quits running after i apply brakes and slow down to make a turn on 1998 Buick Regal

I have replaced the radiator, the starter and the car will just quit running at different intervals after I apply brakes to make a turn it seems. And, sometimes when I start up, the anti-lock brake light and the trac-off light will come on and stay on and then the speedometer needle just goes crazy bounding back and forth. I have had the hoses check also, if electrical, what would cause the car to just stop running?

Asked by for the 1998 Buick Regal
First thing is to check the battery cable connections as a loose or corroded cable will cause intermittent power failure
Could be the ignition switch...not where you place the key though.