I'm not buying the VDI connection either, it is just the last thing they looked at that made it work for a little while longer. Same thing happened this morning, drove it 15+ miles as it appeared normal, stopped for coffee, got back in after 30 minutes and the Service Air Bag message immediately appeared and no A/C controls.
Airbag is alert for the passenger and properly senses an adult ... when the Service Air Bag message isn't on. I mentioned the PSS airbag issues to the dealer so they are aware.
The A/C controls completely die - no fan, no lights on the control dials. Occasionally, they come back on when the airbag warning indicator icon pops up.
The dealer claims they have checked all the ECMs and SCMs, harnesses and fuses for electrical problems. They have cleaned and re-seated the connections to make sure they are tight. All the signs point to an electrical problem but where is the problem source? Did not have this problem before they changed the battery - any ideas on how that might be relevant to a cause?