Reset done, setup wizard done, i did the firmware update to the version 3.2.453 (the router was already on this firmware version but I did the upgrade).
After that, for 5 minutes it was ok, I configured my wifi, I tried to connect my smartphone to the wifi, but at this time, the router did the same thing : 2 wifi lights off, my computer (ethernet) lost the connection to the interface...
Do you have any idea?