OK. Then we have a problem. It has come down to the fact that you do not have the proper testing equipment. It sounds like MECHANICALLY, everything is working correctly. At least PART of the electrical circuits involved seem to be working as well. Here's the problem:
This is what the service information published by the manufacturer states about this code:
Conditions for Running the DTC
* more than 60 minutes has elapsed since the last cold start.
* The system voltage is 9-18 volts.
* The BARO parameter is more than 70 kPa.
* The MAF sensor parameter is less than 33 g/s.
* AIR system is commanded ON.
* Conditions are stable for more than 5 seconds.
* DTC P0411 runs once per trip at start up when the above conditions are met and AIR pump operation is requested.
Conditions for Setting the DTC * The difference between the predicted system pressure and the actual system pressure is more than 6 kPa. * DTC P0411 sets within 22 seconds when the above conditions are met.
1. If any other AIR DTCs are set, perform those diagnostics first.
2. Engine running, observe that the AIR Pressure Sensor parameter approximately equals barometric pressure (BARO).
3. Engine running, enable the AIR pump with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 20-25 kPa above BARO.
4. Engine running, enable the AIR solenoid with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.Circuit/System Testing
So, as you can see, you cannot perform the Circuit/System Verification without the proper scan equipment. A generic code reader cannot even check properly to see if there are any other codes present, so you cannot correctly complete step one.
Most generic OBD code readers are just what hey say they are.....
Most of them can only read GENERIC OBD codes. They cannot read "Manufacturer Specific" codes (which may, or may not be present in your vehicle). The ones that can output manufacturer-specific codes often do not render the correct code description when they do.
Then there is the fact that most of them will only access the "history" portion of the "global" or "generic" side of the computer memory. It will not access the manufacturer side as mentioned above, and it will also not access any "Pending" codes, nor will it access any "current" or "1 Trip" codes, unless they are also recorded in continuous (global) memory.
I have had MANY cars come into my shop where the vehicle owner already went to the local parts store (unbeknown to me) and had them scan the vehicle with their generic scanners.....so they THINK they already know what the problem is with the vehicle before they bring it to me. I scan the vehicle when I bring it into the shop and get the code that the customer already had, PLUS I will get one or 2 more....Trust me on this one, I fight this battle all the time when I tell the customer that there is code "Pxxxx" in their PCM and that I need to diagnose "Blah-Blah" system/circuit....and the customer GOES OFF on me saying That code was NOT in there before...YOU must have done something to my car!!! They refuse to believe that all I did was scan it with the proper equipment....
My best GUESS at this point, is that the computer is not getting the message that the pressure change has occurred - even though it is occurring....like maybe high resistance in the signal return circuit? It is not completely shorted or open, because there are separate codes for those. You really need to see what the computer THINKS is going on.
So, you need to get your hands on a scan tool that can perform the steps listed above before anyone will be able to help you any further with this problem.