Are you using a power injector? If so, you need to add the MAC addrss of the switch port to which it is connected.
Use the show interface <interface name> | include bia command to get the MAC address of the switch port.
power inline negotiation injector <MAC ADDRES>
I have run into this very problem in the field. I hope it helps you with your problem.
Save the configuration and power cycle them. I have seen something similar.
Check your IOS version. I have had to upgrade the IOS version in the past to get the radio to reach an up/up state.
Hope that helps,
Did you somehow recently made an IOS upgrade? If so, make sure you've respected the procedure.
Thanks to ALL,
but now is OK. i just set an SSID on Dot11Radio interface
on Cisco Aironet 1131AG, Dot11Radio interface do not start and will stay to "Reset " Statut until you set an SSID on them.