P0521 means the ECU sees oil pressure sensor readings that don't match expected values for current RPM and oil temperature. Could be a faulty sensor or genuine low oil pressure, and you can't tell which without a mechanical gauge.
P0521 est un code defaut lie a electrique, classe en gravite high. Lorsque le calculateur de ton vehicule detecte cette condition, il enregistre P0521 et allume le voyant moteur.
