I am coming from Ubuntu. Initially my WiFi does not work there either. I can install the proper driver though with sudo apt install bcmwl-kernel-source to get it work work. What is the equivalent on Manjaro? I recognized that there is no apt and the package certainly has a different name too, but I could not find either. I know that I have a broadcom device installed.
03:00.0 Network controller: Broadcom Inc. and subsidiaries BCM4360 802.11ac
Wireless Network Adapter (rev 03)
I will try to install the driver that way. I used my phone as Hotspot and connected to it via Bluetooth. So I installed Manjaro being connected to the internet. I just could not get my WiFi working. Everthing else just worked right away.
Update: Unfortunately pacman tells me that it could not find the target, so I assume that the package name is not correct
I think the correct driver is broadcom-wl
You have two options:
Install the kernel module matching your kernel. For example, in my case: sudo pacman -S linux54-broadcom-wl
Install the dkms kernel module: sudo pacman -S dkms linux54-headers broadcom-wl-dkms (note linux54-headers is kernel specific)
The advantage of 1 is being faster to install and update. The advantage of 2 is the module updating itself automatically upon each kernel update or change. There is no difference concerning performance.