B737NG: High Cabin Diff Pressure
There is a lot of 737NG experience out there which I hope to tap into.
Here is the situation:
You are in cruise flight (ie FL370 or FL390), there are no known faults or MELs, all switches are in their normal position for cruise flight.
You notice that your Cabin Diff needle is in the orange band (8.4 PSI or higher).
There is no master warning
The AUTO FAIL light remains extinguished.
What is the proper reaction if any ?