Morisson
Ставь. Для BCM43142 дрова по ссылке от A.T.W.A. все написано

[[email protected] wh75er]# pacman -Ss broadcom-wl

red
у вас драйвера не загужены

wh75er
02:00.0 Network controller: Broadcom Limited BCM43142 802.11b/g/n (rev 01)
Subsystem: Hewlett-Packard Company Device 804a

A.T.W.A.
А покажи
$ lspci -k
?

[[email protected] ~]$ lspci -k
00:00.0 Host bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series SoC Transaction Register (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: iosf_mbi_pci
00:02.0 VGA compatible controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Integrated Graphics Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: i915
	Kernel modules: i915
00:0b.0 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series Power Management Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: proc_thermal
	Kernel modules: processor_thermal_device
00:13.0 SATA controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series SATA Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: ahci
	Kernel modules: ahci
00:14.0 USB controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series USB xHCI Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: xhci_hcd
	Kernel modules: xhci_pci
00:1a.0 Encryption controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series Trusted Execution Engine (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: mei_txe
	Kernel modules: mei_txe
00:1b.0 Audio device: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series High Definition Audio Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: snd_hda_intel
	Kernel modules: snd_hda_intel
00:1c.0 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCI Express Port #1 (rev 35)
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:1c.2 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCI Express Port #3 (rev 35)
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:1c.3 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCI Express Port #4 (rev 35)
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:1f.0 ISA bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCU (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: lpc_ich
	Kernel modules: lpc_ich
00:1f.3 SMBus: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx SMBus Controller (rev 35)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: i801_smbus
	Kernel modules: i2c_i801
01:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Sun XT [Radeon HD 8670A/8670M/8690M / R5 M330 / M430] (rev 83)
	Kernel driver in use: radeon
	Kernel modules: radeon, amdgpu
02:00.0 Network controller: Broadcom Limited BCM43142 802.11b/g/n (rev 01)
	Subsystem: Hewlett-Packard Company Device 804a
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller (rev 07)
	Subsystem: Hewlett-Packard Company Device 81f2
	Kernel driver in use: r8169
	Kernel modules: r8169

heider
Почему inactive? Должно быть active. От рута сделайте:

[[email protected] wh75er]# systemctl status wpa_supplicant
● wpa_supplicant.service - WPA supplicant
   Loaded: loaded (/usr/lib/systemd/system/wpa_supplicant.service; enabled; vend
   Active: active (running) since Sat 2017-02-25 19:08:49 UTC; 16min ago
 Main PID: 763 (wpa_supplicant)
    Tasks: 1 (limit: 4915)
   CGroup: /system.slice/wpa_supplicant.service
           └─763 /usr/bin/wpa_supplicant -u

Feb 25 19:08:49 koi systemd[1]: Starting WPA supplicant...
Feb 25 19:08:49 koi systemd[1]: Started WPA supplicant.
Feb 25 19:08:49 koi wpa_supplicant[763]: Successfully initialized wpa_supplicant

2017-02-25 19:22:02,676: get_network_device: No WiFi device found, please set this in the preferences.
          Interface doesn't support scanning.

selishii
Для начала неплохо бы посмотреть что есть в системе:
$ lspci |grep WiFi

heider
systemctl status wpa_supplicant
?

[[email protected] ~]$ systemctl status wpa_supplicant
● wpa_supplicant.service - WPA supplicant
   Loaded: loaded (/usr/lib/systemd/system/wpa_supplicant.service; disabled; ven
   Active: inactive (dead)
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