[Konstantinos]

Make sure the table is called PlayerVehicles.

pawn Код:

format(Query, sizeof(Query), "UPDATE `PlayerVehicles` SET Mod1=%d, Mod2=%d, Mod3=%d, Mod4=%d, Mod5=%d, Mod6=%d, Mod7=%d, Mod8=%d, Mod9=%d, Mod10=%d, \
    Mod11=%d, Mod12=%d, Mod13=%d, Mod14=%d, Mod15=%d, Mod16=%d, Mod17=%d WHERE OwnedVehicleID=%d",
    Vehicles[iVehicleID][mod1],
    Vehicles[iVehicleID][mod2],
    Vehicles[iVehicleID][mod3],
    Vehicles[iVehicleID][mod4],
    Vehicles[iVehicleID][mod5],
    Vehicles[iVehicleID][mod6],
    Vehicles[iVehicleID][mod7],
    Vehicles[iVehicleID][mod8],
    Vehicles[iVehicleID][mod9],
    Vehicles[iVehicleID][mod10],
    Vehicles[iVehicleID][mod11],
    Vehicles[iVehicleID][mod12],
    Vehicles[iVehicleID][mod13],
    Vehicles[iVehicleID][mod14],
    Vehicles[iVehicleID][mod15],
    Vehicles[iVehicleID][mod16],
    Vehicles[iVehicleID][mod17],
    iVehicleID);

    print(Query); // Debug
    mysql_query(Query);

Show what it prints and if it still does not update, there's a way.
For example on SQLite, I can execute SQL from a database editor, if there is error, it says which one.