Driving the Suburban and it losses all electrical power. It stops working on the road and the screens and instruments stop working on the dash.

This is the third times this has happened and it was reported to ONSTAR. The vehicle restarts but the screen had reset to speedometer and midnight clock setting. Went to the dealer after the second incident they had an error code on the adaptive cruse controller. They changed the control unit for $1125. Drove for a month and 600 miles and the electrical system failed again with my wife driving this time (just yesterday). It was restarted again and the failure reset the screen settings again.

The driving speeds were low (under 30 mph) each time the power failed and the brakes and steering were like a tank of course but it stopped. These outages are affecting the main power supply to the vehicle and creating a very unsafe condition. The dealer who has been responsive but says it can be anything from a minor connection problem to a intermittent component failure. They can't tell until they investigate the further. When does this thing end? The vehicle functions well and is excellent WHEN it works.

Why would one connection/component interruption cause the entire vehicle to shut down without warning? Is this a design flaw in the electrical or software component by GM? Is everything electrical on the vehicle locked into together like a house of cards? One thing fails - they all fall down.