I don't understand what disconnecting the battery is supposed to accomplish.
Use the scan tool to clear all the trouble codes even if you think there aren't any. Run the engine afterwards, and it see if it will achieve closed-loop operation.
What, if any, trouble codes come back? No pending codes?
What scan tool are you using? Do you have VIN-specific operation for this vehicle, or is it working on "generic" OBD 2 settings? Does it work properly on other vehicles?
Use the scan tool to clear all the trouble codes even if you think there aren't any. Run the engine afterwards, and it see if it will achieve closed-loop operation.
What, if any, trouble codes come back? No pending codes?
What scan tool are you using? Do you have VIN-specific operation for this vehicle, or is it working on "generic" OBD 2 settings? Does it work properly on other vehicles?