Provavelmente você precisa instalar o driver correto desta maneira:
sudo apt-get purge bcmwl-kernel-source
sudo apt-get install firmware-b43-installer
Instalei o driver, mas nenhuma rede sem fio aparece no gerenciamento da rede. Uma mensagem apareceu dizendo que a detecção automática está desativada. Esta é a informação que recebi da solução de problemas da rede sem fio link
########## wireless info START ##########
Report from: 16 Jan 2017 14:59 CST -0600
Booted last: 16 Jan 2017 14:29 CST -0600
Script from: 08 Jul 2016 02:16 UTC +0000
##### release ###########################
Distributor ID: Ubuntu
Description: Ubuntu 14.04.5 LTS
Release: 14.04
Codename: trusty
##### kernel ############################
Linux 4.4.0-59-generic #80~14.04.1-Ubuntu SMP Fri Jan 6 18:02:23 UTC 2017 i686 i686 i686 GNU/Linux
Parameters: ro, quiet, splash, vt.handoff=7
##### desktop ###########################
Ubuntu
##### lspci #############################
02:00.0 Ethernet controller [0200]: Broadcom Corporation NetXtreme BCM57765 Gigabit Ethernet PCIe [14e4:16b4] (rev 10)
Subsystem: Broadcom Corporation NetXtreme BCM57765 Gigabit Ethernet PCIe [14e4:16b4]
Kernel driver in use: tg3
03:00.0 Network controller [0280]: Broadcom Corporation BCM4331 802.11a/b/g/n [14e4:4331] (rev 02)
Subsystem: Broadcom Corporation BCM4331 802.11a/b/g/n [14e4:4331]
04:00.0 FireWire (IEEE 1394) [0c00]: LSI Corporation FW643 [TrueFire] PCIe 1394b Controller [11c1:5901] (rev 08)
##### lsusb #############################
Bus 002 Device 004: ID 192f:0416 Avago Technologies, Pte. ADNS-5700 Optical Mouse Controller (3-button)
Bus 002 Device 003: ID 05ac:8242 Apple, Inc. Built-in IR Receiver
Bus 002 Device 002: ID 0424:2513 Standard Microsystems Corp. 2.0 Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 003: ID 05ac:8509 Apple, Inc. FaceTime HD Camera
Bus 001 Device 005: ID 05ac:0252 Apple, Inc. Internal Keyboard/Trackpad (ANSI)
Bus 001 Device 008: ID 05ac:821a Apple, Inc. Bluetooth Host Controller
Bus 001 Device 004: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 001 Device 002: ID 0424:2513 Standard Microsystems Corp. 2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
##### PCMCIA card info ##################
##### rfkill ############################
0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
##### lsmod #############################
##### interfaces ########################
auto lo
iface lo inet loopback
##### ifconfig ##########################
eth0 Link encap:Ethernet HWaddr 40:6c:8f:20:12:3b
inet addr:192.168.1.73 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: 2602:30a:c044:ed70::40/128 Scope:Global
inet6 addr: fe80::426c:8fff:fe20:123b/64 Scope:Link
inet6 addr: 2602:30a:c044:ed70:426c:8fff:fe20:123b/64 Scope:Global
inet6 addr: 2602:30a:c044:ed70:9df:87e7:8915:4f30/64 Scope:Global
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:21845 errors:0 dropped:0 overruns:0 frame:0
TX packets:16191 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:22427826 (22.4 MB) TX bytes:1832471 (1.8 MB)
Interrupt:16
##### iwconfig ##########################
lo no wireless extensions.
eth0 no wireless extensions.
##### route #############################
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.1.254 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth0
##### resolv.conf #######################
nameserver 127.0.1.1
search attlocal.net
##### network managers ##################
Installed:
NetworkManager
Running:
root 853 1 0 14:29 ? 00:00:03 NetworkManager
##### NetworkManager info ###############
NetworkManager Tool
State: connected (global)
- Device: eth0 [Wired connection 1] -------------------------------------------
Type: Wired
Driver: tg3
State: connected
Default: yes
HW Address: 40:6C:8F:20:12:3B
Capabilities:
Carrier Detect: yes
Speed: 1000 Mb/s
Wired Properties
Carrier: on
IPv4 Settings:
Address: 192.168.1.73
Prefix: 24 (255.255.255.0)
Gateway: 192.168.1.254
DNS: 192.168.1.254
IPv6 Settings:
Address: 2602:30a:c044:ed70::40
Prefix: 128
Gateway: fe80::ea33:81ff:fe68:ed90
Address: 2602:30a:c044:ed70:9df:87e7:8915:4f30
Prefix: 64
Gateway: fe80::ea33:81ff:fe68:ed90
Address: 2602:30a:c044:ed70:426c:8fff:fe20:123b
Prefix: 64
Gateway: fe80::ea33:81ff:fe68:ed90
Address: fe80::426c:8fff:fe20:123b
Prefix: 64
Gateway: fe80::ea33:81ff:fe68:ed90
Address: 2602:30a:c044:ed70::40
Prefix: 128
Gateway: ::
##### NetworkManager.state ##############
[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true
WimaxEnabled=true
##### NetworkManager.conf ###############
[main]
plugins=ifupdown,keyfile,ofono
dns=dnsmasq
no-auto-default=40:6C:8F:20:12:3B,
[ifupdown]
managed=false
##### NetworkManager profiles ###########
Provavelmente você precisa instalar o driver correto desta maneira:
sudo apt-get purge bcmwl-kernel-source
sudo apt-get install firmware-b43-installer