diff --git a/testing/marionette/client/marionette/b2ginstance.py b/testing/marionette/client/marionette/b2ginstance.py
index 6fdace8dc678..3a3b894591cb 100644
--- a/testing/marionette/client/marionette/b2ginstance.py
+++ b/testing/marionette/client/marionette/b2ginstance.py
@@ -76,7 +76,7 @@ class B2GInstance(object):
                 return option
         raise Exception('%s not found!' % binary)
 
-    def __init__(self, homedir=None, devicemanager=None):
+    def __init__(self, homedir=None, devicemanager=None, emulator=False):
         if not homedir:
             homedir = self.find_b2g_dir()
         else:
@@ -87,7 +87,7 @@ class B2GInstance(object):
 
         self.homedir = homedir
         self.adb_path = self.check_adb(self.homedir)
-        self.fastboot_path = self.check_fastboot(self.homedir)
+        self.fastboot_path = None if emulator else self.check_fastboot(self.homedir)
         self.update_tools = os.path.join(self.homedir, 'tools', 'update-tools')
         self._dm = devicemanager
 
diff --git a/testing/marionette/client/marionette/emulator.py b/testing/marionette/client/marionette/emulator.py
index 3ca6f7c12606..e804164006bf 100644
--- a/testing/marionette/client/marionette/emulator.py
+++ b/testing/marionette/client/marionette/emulator.py
@@ -74,7 +74,7 @@ class Emulator(object):
         self.copy_userdata = self.dataImg is None
 
     def _check_for_b2g(self):
-        self.b2g = B2GInstance(homedir=self.homedir)
+        self.b2g = B2GInstance(homedir=self.homedir, emulator=True)
         self.adb = self.b2g.adb_path
         self.homedir = self.b2g.homedir
 
@@ -277,7 +277,7 @@ waitFor(
         marionette.delete_session()
 
     def connect(self):
-        self.adb = B2GInstance.check_adb(self.homedir)
+        self.adb = B2GInstance.check_adb(self.homedir, emulator=True)
         self.start_adb()
 
         online, offline = self._get_adb_devices()