Flame out. Restarted after few minutes
 

When the engine flamed out, no dashboard lights showing. Turned key off & on and all normal dashboard lights lit up but no engagement of starter to start engine. After a few minutes the engine started as normal. Drove 40 miles w/o incident and a Volvo dealer determined no codes appeared.

Check the cable bolted to top of the positive battery cable, and make sure it's clean and tight. Do the same with the power connection to the fuse box labeled "MAIN FUSES" under the hood, and also check the cable.