If the problem is intermittent and corects itself, the warning lights will not flash, but a code will be stored in memory. Sometimes running the shifter back and forth rapidly a few times will clean up the switch contacts, and the problem goes away for awhile. The most common time for the problems I described to occur is when the ambient temp is low. Don't see toomany failures when the weather is warm. Check for fault codes in socket A-1 anyway and repost. At least you will have an idea what happened.