How to the reset options or factory settings bootloader

Hello everyone

I have a pixhawk 2.4.8, after the whole process of calibration and setup with the QGroundcontrol (in mac) I could fly a few days without any problem … then I make tuning adjustments (with APMplaner in mac).

As a result the pixhawk no longer flies, it has many problems of accelerometers and GPS (problems that after 4 months testing everything that exists in I can not solve)

The reason for my mix of these 2 programs is that in QGroundcontrol I do not have enough tools like in APMplaner.

After finding the problem I look for a solution, and try all the reset options or factory settings but I do not manage to leave them as virgins factory.

I tried the bootloader and everything seems to work out fine, but I still have problems with the red flashing light

any ideas???