diff --git a/tests/modules/test_brightness.py b/tests/modules/test_brightness.py
index b636d44..5582bcc 100644
--- a/tests/modules/test_brightness.py
+++ b/tests/modules/test_brightness.py
@@ -10,6 +10,7 @@ except ImportError:
 
 import tests.mocks as mocks
 
+from bumblebee.config import Config
 from bumblebee.input import WHEEL_UP, WHEEL_DOWN
 from bumblebee.modules.brightness import Module
 
@@ -20,9 +21,9 @@ class TestBrightnessModule(unittest.TestCase):
     def tearDown(self):
         mocks.teardown_test(self)
 
-    def test_format(self):
-        for widget in self.module.widgets():
-            self.assertEquals(len(widget.full_text()), len("100%"))
+    # def test_format(self):
+    #     for widget in self.module.widgets():
+    #         self.assertEquals(len(widget.full_text()), len("100%"))
 
     def test_wheel_up(self):
         mocks.mouseEvent(stdin=self.stdin, button=WHEEL_UP, inp=self.input, module=self.module)
@@ -38,10 +39,20 @@ class TestBrightnessModule(unittest.TestCase):
         mocks.mouseEvent(stdin=self.stdin, button=WHEEL_DOWN, inp=self.input, module=module)
         self.popen.assert_call("xbacklight -10%")
 
-    def test_update(self):
-        self.popen.mock.communicate.return_value = ("20.0", None)
+    @mock.patch('bumblebee.modules.brightness.open', create=True)
+    def test_update(self, mock_open):
+        mock_open.side_effect = [
+                mock.mock_open(read_data="20").return_value,
+                mock.mock_open(read_data="100").return_value
+                ]
         self.module.update_all()
         self.assertEquals(self.module.brightness(self.anyWidget), "020%")
+        self.assertEquals(len(self.module.brightness(self.anyWidget)), len("100%"))
 
+    @mock.patch('bumblebee.modules.brightness.open')
+    def test_error(self,mock_open):
+        mock_open.side_effect = FileNotFoundError
+        self.module.update_all()
+        self.assertEquals(self.module.brightness(self.anyWidget), "n/a")
 
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