diff --git a/selfdrive/car/interfaces.py b/selfdrive/car/interfaces.py
index ca83cabb7d..3639b2836e 100644
--- a/selfdrive/car/interfaces.py
+++ b/selfdrive/car/interfaces.py
@@ -23,9 +23,10 @@ class CarInterfaceBase():
     self.frame = 0
     self.low_speed_alert = False
 
-    self.CS = CarState(CP)
-    self.cp = self.CS.get_can_parser(CP)
-    self.cp_cam = self.CS.get_cam_can_parser(CP)
+    if CarState is not None:
+      self.CS = CarState(CP)
+      self.cp = self.CS.get_can_parser(CP)
+      self.cp_cam = self.CS.get_cam_can_parser(CP)
 
     self.CC = None
     if CarController is not None: