This hardware doesn't work with b43 kernel driver for Broadcom cards.
You need to install binary-only driver with broadcom-sta-dkms package. Because of the license, it is located under non-free section so your backports repository configuration line in
/etc/apt/sources.list file must also include non-free section like below:
deb http://http.debian.net/debian jessie-backports main contrib non-free
After checking apt sources.list file, you can install driver:
$ sudo apt-get update
$ sudo apt-get install -t jessie-backports broadcom-sta-dkms
Your wireless card start to work again on next boot.
Secondly, it seems that your wireless regulatory domain is not set. You may have some connection problems if this is not set properly. You can check current settings with:
$ sudo iw reg get
If there is no setting made or setting made for wrong country, check your two letter country code from ISO 3166 Country Codes and set it like that:
$ sudo iw reg set TR
To make this settings permanent, you have to edit
/etc/default/crda file and set REGDOMAIN variable to your country code like that: