car seemed to have lost elec power; no locks, lights, anything. When key in ignition is turned on dash panel comes on but no crank. With key out 2 dashes on either side of hvac display. Any thoughts or help from those of you who know more than me would be appreciated. Thanks

found shock damper relay hot and steady popping, removed and changed, power restored. Any one know how to determine whether external problem caused relay failure or the relay failed by itself?

Wow nobody wants to chime in on this. Probably just a faulty relay. If it happens again I would be looking at the shock itself.

This advice is not from experience only my knowledge of electrical systems.

found shock damper relay hot and steady popping, removed and changed, power restored. Any one know how to determine whether external problem caused relay failure or the relay failed by itself?

There is a good chance that whatever started this chain of events set a trouble code (DTC). Use this thread to retrieve the codes http://www.cadillacforums.com/forums/cadillac-tech-tips/72494-how-pull-codes.html

The codes you are most interested in will be "B" and "C" codes and identified as "History" since the trouble is no longer occuring.