A guess as I have a Peugeot Partner Escapade MPV.
the dash display on mileage shows on starting the state of oil level then switches back to mileage.
Have you check the oil level when engine cold and vehicle on flat ground?. If reading is ok on dip stick, should be just below full mark, never over fill always keep it slightly lower than full. If the level is ok then its a garage job as it must be something to do with the sensor. Check with your peugeot garage what they mean if it's nothing to do with oil.
BB, February 2011
