When you replaced the Compressor and the Air Bag (which as Grit Valve says, should ideally be done in pairs) did you get it on diagnostics to clear any fault codes??
The ECUs log and store some faults that won't clear until you plug in the computer....just replacing components doesn't clear these faults...
Also if the battery has got weak or disconnected, have you reset the steering angle sensor by turning full lock left then full lock right and back to centre....as the EAS fault message appears along with the HDC inactive message if you haven't reset the SaS on battery reconnection....
put your location in your profile, there maybe some local to you with the gear to reset it for you!
I am not sure the All Comms does 55 plates....it goes up to vin number 5A999999...