Volvo ishift and sir dryer???

I have a question, got a 2012 vnl ishift, just going down to the road the other day and suddenly the truck just goes to idle,trans light comes on,I hit the shoulder and truck was still in 12 would go into neutral,but would go into reverse. After playing with the .m shifter for a couple minutes it goes to neutral and I shut it of and restart it.it would take off but really didn't want to shift. Got it to get back to highway speeds 5 miles down it did the same. But Truck had a strange idle. got it to the shop they said it had multiple codes but I had a aftermarket air dryer on and it wasn't supplying the correct air for the transmission. Mind you I've had that dryer on for about 8 months. After the new factory air dryer install 200 miles so far and no issues. Has any had this type of problem with this type of solution? Thanks in advance .

 

Welp,that definitely wasn't it about 450 miles or so she acted up again. It doesn't seem mechanical more electronic.