2.2 2005 low oil pressure and depollution system

[Amandasw]

Had a strange adventure with my Peugeot 407 2.2 2005 the other day and I don't understand anything. The car has been running fine until this happened. Drove on the highway, suddenly the engine dies and the screen shows that the EPS is not working and "depollution system faulty". A friend tows us home. The next day I read about the usual error that fuse f10 in the fuse box can break, then fed power directly to the fuse and then the car started without any problems. The EPS error message was gone but the depollution system error message remained. Another day later, we're going to run a small errand, but after backing out just a few meters from the garage, we get the low oil pressure symbol on the display. We look at the dipstick but we see no oil at all, note that it has been very cold these days around -20 celsius. We fill about 2 liters of oil, start the car again and then there are no strange things at all. The only error message that remains is still "depollution system faulty" along with the engine light but the car runs flawlessly. What to believe, investigate and do?

[PaulC5]

Plug in a fault code reader to see what the error message is by getting the fault code. If you do not have a code reader any garage will have one.