Wireless connection not working. Can connect through ethernet cable. Using Lenovo.

Hii! I am new to Ubuntu
My wireless connection worked very well on Windows and Ubuntu 9.04
But it is not working now.
I am using Ubuntu 12.04 LTE on the Lenovo G Series laptop.
I tried the codes given on the forum.

rakesh@rakesh-C-Notebook-XXXX:~$ lspci -nn | grep 0280
03:00.0 Network controller [0280]: Broadcom Corporation BCM4311 802.11b/g WLAN [14e4:4311] (rev 01)
rakesh@rakesh-C-Notebook-XXXX:~$ rfkill list all
1: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
2: ideapad_bluetooth: Bluetooth
Soft blocked: no
Hard blocked: no
3: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
rakesh@rakesh-C-Notebook-XXXX:~$ lsmod | grep -e brcmsmac -e wl
wl 2646601 0
lib80211 14040 1 wl
rakesh@rakesh-C-Notebook-XXXX:~$ sudo modprobe -r wl
[sudo] password for rakesh:
rakesh@rakesh-C-Notebook-XXXX:~$ lsmod | grep -e brcmsmac -e wl
(showed nothing)
rakesh@rakesh-C-Notebook-XXXX:~$ iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

rakesh@rakesh-C-Notebook-XXXX:~$ sudo iwlist wlan0 scan
wlan0 Interface doesn't support scanning.

rakesh@rakesh-C-Notebook-XXXX:~$ sudo modprobe brcmsmac
(showed nothing)
rakesh@rakesh-C-Notebook-XXXX:~$

I can only connect through ethernet cable.
Please help me so that I dont have to shift back to Windows.

Please see here. You have the same device and require the same fix.

http://askubuntu.com/questions/22882...ers-installed/

Thanks for quick response. It did not work.
I tried the codes that you recommended.
sudo apt-get remove --purge bcmwl-kernel-source sudo apt-get install linux-firmware-nonfree sudo modprobe b43
this is what I got.
rakesh@rakesh-C-Notebook-XXXX:~$ sudo apt-get remove --purge bcmwl-kernel-source
[sudo] password for rakesh:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
linux-headers-3.2.0-29 linux-headers-3.2.0-29-generic-pae dkms
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
bcmwl-kernel-source*
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 3,252 kB disk space will be freed.
Do you want to continue [Y/n]? Y
(Reading database ... 170903 files and directories currently installed.)
Removing bcmwl-kernel-source ...
Removing all DKMS Modules
Done.
update-initramfs: deferring update (trigger activated)
Purging configuration files for bcmwl-kernel-source ...
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools ...
update-initramfs: Generating /boot/initrd.img-3.2.0-34-generic-pae

rakesh@rakesh-C-Notebook-XXXX:~$ sudo apt-get install linux-firmware-nonfree
Reading package lists... Done
Building dependency tree
Reading state information... Done
linux-firmware-nonfree is already the newest version.
The following packages were automatically installed and are no longer required:
linux-headers-3.2.0-29 linux-headers-3.2.0-29-generic-pae dkms
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

rakesh@rakesh-C-Notebook-XXXX:~$ sudo modprobe b43
(showed nothing)
rakesh@rakesh-C-Notebook-XXXX:~$

Please Help.

Do you have a wireless interface, ideally wlan0?

Code:

---

iwconfig

---

Does it scan and see networks?

Code:

---

sudo iwlist wlan0 scan

---

Is the wireless switch on or off?

Code:

---

rfkill list all

---

YOU ARE GREAT CHILI! I think all it needed was a restart. After the restart now I am replying through wireless connection.

The codes that you wanted me to run:-

rakesh@rakesh-C-Notebook-XXXX:~$ iwconfig
lo no wireless extensions.

wlan0 IEEE 802.11bg ESSID:"linksys"
Mode:Managed Frequency:2.462 GHz Access Point: 00:21:29:68:05:52
Bit Rate=54 Mb/s Tx-Power=20 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=70/70 Signal level=-40 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:90 Missed beacon:0

rakesh@rakesh-C-Notebook-XXXX:~$ sudo iwlist wlan0 scan
[sudo] password for rakesh:
wlan0 Scan completed :
Cell 01 - Address: 00:21:29:68:05:52
Channel:11
Frequency:2.462 GHz (Channel 11)
Quality=70/70 Signal level=-40 dBm
Encryption key:off
ESSID:"linksys"
Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
12 Mb/s; 24 Mb/s; 36 Mb/s
Bit Rates:9 Mb/s; 18 Mb/s; 48 Mb/s; 54 Mb/s
Mode:Master
Extra:tsf=000000092ba7cf8b
Extra: Last beacon: 20ms ago
IE: Unknown: 00076C696E6B737973
IE: Unknown: 010882848B960C183048
IE: Unknown: 03010B
IE: Unknown: 0706444520010D14
IE: Unknown: 2A0100
IE: Unknown: 32041224606C

rakesh@rakesh-C-Notebook-XXXX:~$ rfkill list all
0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
1: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
2: ideapad_bluetooth: Bluetooth
Soft blocked: no
Hard blocked: no
3: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
rakesh@rakesh-C-Notebook-XXXX:~$

Thanks a lot Chili.

Great job. Please use thread tools at the top to mark Solved.