I have started having a weird problem: I start the car and it idles fine. after about 5-10 mins it completely shuts off and won't start again for about another 20 mins. while in shut down mode I get no readings ie clock, odometer, radio. After it starts again I have 2 or 3 different fail codes: check airbag system urgent, check engine, you may have reduced performance. The check engine light and the bulb out lights stay on. I have had the software up graded, which is what the dealer said was necessary. But it happened again today less than a month after the upgrade. This happening to anyone?