HT4628 my powerbook g4 os x 10.5.8 leopard is showing-Connection time out while connecting to the wifi.however it showing all available wifi connections around but not connecting it..however ethernet is working

Question

Problem while connecting with Wi-Fi,
When i am connecting my powerbook g4 leopard  to any Wi-fi connection it showing -Connection time out, however Ethernet is working .I have updated all softwares but still same problem.

Answer 1

It's possible that either the internal AirPort Extreme card or the antenna is faulty or has failed.
One last thing to try before going with another Wi-Fi solutions is to the following:
Try the following, in order, until (hopefully) resolved:
1a. Delete Preferred Network(s)
System Preferences > Network > AirPort > Advanced > AirPort tab
Under "Preferred Networks," delete the network(s) you regularly use from the list.
1b. Delete AirPort Keychain Entries
Launch the "Keychain Access" application located in Applications/Utilties.
Click on the "Kind" filter at the top, and look for any "AirPort network password" entries...and delete them.
1c. Add Preferred Network(s)
System Preferences > Network > AirPort > Advanced > AirPort tab
Add the preferred network(s) using the "+" button.
Restart or log out then back in.
2. Move System Configuration Files
(Note: You will have to reestablish your network connections settings.)
Go to /Library/Preferences
Move the SystemConfiguration folder to the desktop.
Restart your Mac. (Note: OS X will rebuild the files that are now sitting on your desktop. If this doesn't resolve the issue, you can move the folder back to it's original location.)
3. Run the Disk Utility to repair Disk Permissions.
Restart or log out then back in.
4. Turn off the Mac OS X Firewall
System Preferences > Sharing > Firewall
Click the "Stop" button.
5. Create a New User Account
System Preferences > Accounts
Click "+" to add a new account
Log off, then log back on with the new user account.
Try connecting with the AirPort.
If none of these help resolve the issue, you may want to consider getting a USB wireless adapter to replace both the internal card and antenna. One such vendor of these adapters is Other World Computing (OWC).